Sunlight is essential for regulating our sleep patterns and producing vitamin D, which is vital for normal bone function and overall health. However, excessive exposure to sunlight can be harmful. Chronic exposure to ultraviolet (UV) radiation in sunlight is a known cause of nonmelanoma skin cancer. UV rays are classified into two types: UVA and UVB. UVB rays are shorter and can cause sunburn, while UVA rays are longer and can penetrate more deeply into the skin.
UVA rays contribute to skin aging and skin cancer, as they can pass through window glass and are emitted by lamps and tanning booths. A tan induced by UVA rays, such as from a tanning bed, provides 5-10 times less protection against subsequent UV exposure compared to a tan induced by UVB rays. This is because UVA-induced tans result in less noticeable thickening of the epidermis and hyperkeratosis, making the skin more susceptible to damage. UVA rays also suppress the immune system, affecting primary and memory T cell function, and are constant throughout the day and year. UVB rays, while also leading to skin aging and cancer, are more intense during summer, midday, at higher altitudes, and closer to the equator.
Skin cancer is the most common form of cancer in the U.S., with basal cell carcinoma (BCC) being the most prevalent type. BCC typically appears in sun-exposed areas like the face, scalp, ears, chest, back, and legs. These tumors often present as small, dome-shaped bumps with a pearly white color or as recurring sores that bleed, heal, and reappear. An estimated 3.6 million cases of BCC are diagnosed annually in the U.S. More people are diagnosed with skin cancer each year in the U.S. than all other cancers combined, with 1 in 5 Americans developing skin cancer by age 70. The U.S. experiences over two skin cancer-related deaths every hour, and having five or more sunburns doubles the risk of developing melanoma. If melanoma is detected early, the five-year survival rate is as high as 99%.
The International Agency for Research on Cancer, part of the World Health Organization, classifies UV tanning devices as Group 1 carcinogens, a category that also includes plutonium, cigarettes, and solar UV radiation. Risk factors for skin cancer, aside from chronic UV exposure, include light complexion, light eyes, blonde or red hair, freckles, poor tanning ability, easy sunburning, numerous moles, genetics, and history of blistering sunburns.
Preventing skin cancer involves protecting oneself from UV rays by avoiding tanning beds and using sunscreen or protective clothing. Sunscreen contains Sun Protection Factor (SPF), with broad-spectrum SPF covering both UVA and UVB rays. There are two main types of sunscreens: chemical and mineral (or physical). Both are effective and available over the counter. Mineral sunscreens, containing zinc oxide or titanium dioxide, reflect and scatter harmful rays and are usually thick and white, requiring time to rub into the skin. They should be applied at least 15 minutes before sun exposure and are preferred for lighter skin and drier skin types.
Chemical sunscreens also protect against UVA and UVB rays, but some formulations may not fully cover UVA rays. Active ingredients include avobenzone, octinoxate, and oxybenzone. These sunscreens absorb into the skin, where they convert UV rays into heat and release them from the body. Chemical sunscreens do not need to be applied 15 minutes before sun exposure, as they work upon direct contact with the skin. They tend to apply more evenly, do not leave a white cast, and are often more sweat-resistant than mineral sunscreens.
Hung M, Beazer IR, Su S, Bounsanga J, Hon ES, Lipsky MS. An Exploration of the Use and Impact of Preventive Measures on Skin Cancer. Healthcare (Basel). 2022 Apr 15;10(4):743. doi: 10.3390/healthcare10040743. PMID: 35455920; PMCID: PMC9025621.
Sander, Megan et al. “The efficacy and safety of sunscreen use for the prevention of skin cancer.” CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne vol. 192,50 (2020): E1802-E1808. doi:10.1503/cmaj.201085
Sunscreen has become an integral part of one’s daily skincare routine. With companies releasing new products and formulations, people have many options to choose from. Each sunscreen has different characteristics and may set differently on various types of skin. Sunscreen works to protect against UV radiation. It has usually been primarily used for sunburn prevention. However, with the progressing science industry, we can see the importance of protecting ourselves against skin cancer, skin damage, and skin aging. In the past few decades, many studies have been conducted to formally assess the efficacy of sunscreens. Online influencers even perform at-home self-studies to compare the latest sunscreens on the market. Several randomized controlled trials displayed a reduction in the risk of squamous cell and melanoma cancers. Skin cancer is one of the most common cancers in the United States, requiring adequate protection against UVR.
Sunscreens are available as sprays, gels, lotions, and solid blocks. However, there are two main types of sunscreen: chemical and mineral. Mineral sunscreens contain minerals such as zinc oxide and titanium oxide which sit on top of the skin upon application. Chemical sunscreens, on the other hand, get absorbed into the skin. Mineral sunscreens reflect UV rays, whereas chemical sunscreens, which contain UV filters such as oxybenzone and octinoxate, deactivate the rays upon absorption into the skin. Mineral sunscreens have immediate effectiveness while chemical sunscreens take approximately 20 minutes to fully work. As mineral sunscreens contain an astringent such as zinc oxide, it’s more likely to cause dryness. The minerals cause the sunscreen to have a thicker consistency which may lead to a white cast formed on the skin. This makes it difficult for individuals with darker skin to find an appropriate sunscreen. Many people may opt for chemical sunscreens due to their hydrating abilities, lack of a whitecast, and blendability. However, due to their active ingredients, individuals are more likely to experience allergic reactions, irritation, and clogged pores. The FDA has even inquired into the UV filters used in chemical sunscreens, stating the absorption into the skin, into the bloodstream, may negatively impact one's health. Although no official statement has been released, many have stated that the benefits of protection against skin cancer outweigh the risks.
Sunscreens state their SPF, otherwise known as, sun protection factor. This measures how much the product will protect you from UVB and UVA rays. It is important to use a minimum of SPF 30. It may be a game of trial and error in the beginning before you select the product that works for you. One thing that many individuals, myself included, forget to do is reapply sunscreen. Sunscreen usually needs to be reapplied every 2 hours. Sunscreen also needs to be reapplied after swimming or sweating. It is also a misconception to wear sunscreen on sunny days. UV rays are still present on a cloudy day. Many medications such as benzoyl peroxide, doxycycline, and voriconazole require sun protection, or else photosensitivity reactions such as redness, itchiness, pain, and rash may occur. Individuals should educate themselves about the benefits of sun protection and research which products work best for their skin.
Skin cancer is a widespread form of cancer, with millions of new cases diagnosed annually. Its primary cause is exposure to ultraviolet (UV) radiation from the sun, which can harm the DNA in skin cells, leading to mutations that may result in cancerous growths. However, the risk of developing skin cancer can be significantly lowered by using sunscreen.
Sunscreen as we know is a topical product applied to the skin to shield it from the harmful effects of UV radiation. It functions by absorbing or reflecting UV radiation, thus preventing it from penetrating the skin and causing damage. Available in various formulations such as lotions, creams, gels, sprays, and sticks, sunscreens differ in their sun protection factor (SPF) and the types of UV radiation they guard against.
SPF indicates a sunscreen's ability to protect the skin from UVB radiation, the primary cause of sunburn and a significant factor in skin cancer development. The higher the SPF value, the greater the protection provided. For instance, SPF 30 sunscreen shields against about 97% of UVB radiation, while SPF 50 sunscreen protects against about 98%. Using sunscreen with an SPF of at least 30 is recommended for adequate protection.
Apart from SPF, it's crucial to consider the broad-spectrum protection offered by sunscreen. Broad-spectrum sunscreens shield against both UVA and UVB radiation. UVA radiation penetrates the skin more deeply than UVB radiation and can lead to premature skin aging and an elevated risk of skin cancer. Hence, using a broad-spectrum sunscreen helps protect against both types of UV radiation.
When applying sunscreen, it's important to cover all exposed areas generously at least 15-30 minutes before going outside. This allows the sunscreen to absorb fully and provide maximum protection. Reapply sunscreen every two hours or immediately after swimming, sweating, or towel drying, as these activities can reduce its effectiveness.
Despite sunscreen's benefits, studies show that many people do not use it consistently or correctly, leading to inadequate protection and an increased risk of skin cancer. Educating the public about sun protection's importance and the correct application of sunscreen is essential to encourage its proper use.
In conclusion, sunscreen plays a crucial role in shielding the skin from UV radiation's harmful effects and reducing the risk of developing skin cancer. By using broad-spectrum sunscreen with an adequate SPF and applying it correctly and consistently, individuals can safely enjoy the sun while minimizing their risk of skin cancer.
References:
Hung M, Beazer IR, Su S, Bounsanga J, Hon ES, Lipsky MS. An Exploration of the Use and Impact of Preventive Measures on Skin Cancer. Healthcare (Basel). 2022 Apr 15;10(4):743. doi: 10.3390/healthcare10040743. PMID: 35455920; PMCID: PMC9025621.
The Importance of Sunscreen in Preventing Skin Cancer
Sunscreen is a fundamental component of a healthy skincare routine, playing a pivotal role in safeguarding the skin against the damaging effects of ultraviolet (UV) radiation from the sun. Beyond its benefits, such as preventing sunburn and premature aging, the importance of sunscreen extends to the prevention of more severe consequences like skin cancer. As a crucial line of defense, sunscreen helps shield the skin from harmful UVA and UVB rays, emphasizing the significance of incorporating this protective measure into daily skincare practices. This introduction explores the importance of sunscreen in preventing skin cancer.
To understand how sunscreen can prevent skin cancer, we must understand how UV rays work. There are three types of UV rays: UVA, UVB, and UVC. UVC radiation is removed by the ozone layer, thus UVA and UVB cause the most damage. UVA rays reach all the way into the dermis, while UVB rays reach the top layer of the dermis. UVA rays are passed through car passenger windows, produced by lamps and tanning booths, and are constant throughout the day and year. UVA rays penetrate more deeply than UVB rays and they are used in tanning booths to produce a tan. These tans increase your risk of skin cancer and provide less protection from sun exposure than a UVB ray tan. UVB rays are responsible for most skin damage like sunburns, as these rays are more intense in the summer, midday, at high altitudes, and closer to the equator. In addition to UV risk, those with a light complexion, light eyes, blonde or red hair, many freckles, tan poorly/sunburn easily, and many moles are at a higher risk of skin cancer through sun exposure.
There are physical ways of blocking the sun that should be recommended to all patients. For example, wearing protective clothing such as long pants, a long sleeved shirt, and a hat with a wide brim. Clothing items that are tightly woven and dark in color can block out more UVR. For high risk patients, those spending more time in the sun during peak times, sunscreen should be utilized. Complete avoidance of UVR is key to preventing UVR induced skin disorders. Although we understand, that is not feasible for everyone. We should equip our patients with the necessary tools and information to pick out the best sunscreen for them.
SPF is a common term everyone is familiar with. It stands for sun protection factor. The SPF value is calculated based on the ratio of the time it takes for UVB radiation to cause noticeable redness on the skin with the sunscreen versus without it. For example, if a person typically starts to experience sunburn after 10 minutes of sun exposure without sunscreen, applying sunscreen with SPF 30 theoretically extends that time to 300 minutes (10 minutes x 30 SPF).SPF15+ is recommended for all patients. At this protection factor, UVA and UVB protection are also guaranteed. The FDA regulates sunscreens to make sure their effectiveness is met. The FDA has proposed that it is not necessary to use an SPF over 60, as there are no significant differences in benefits shown with a higher SPF.
Additionally, there are two different types of topical sunscreens: chemical and physical. Chemical sunscreens use organic compounds like avobenzone or oxybenzone to absorb UV radiation and convert it into heat, which is then released from the skin. Physical sunscreens contain minerals like zinc oxide or titanium dioxide that form a physical barrier on the skin that reflects UV rays. Some prefer chemical sunscreens as it leaves less of a white cast but physical sunscreens can block both UVB and UVA rays.
In short, to understand how skin cancer can be prevented, one must understand the importance of sunscreen and its ability to block UV rays.
Kimberly M. Crosby, (2020), "Chapter 39: Prevention of Sun-Induced Skin Disorders," Handbook of Nonprescription Drugs: An Interactive Approach to Self-Care, 20th Edition https://doi-org.jerome.stjohns.edu/10.21019/9781582123172.ch39
Sunlight is essential for the human body to keep our sleeping patterns on track and producing vitamin D, which is important for normal bone function and health. However, just like anything else, being exposed to too much of something is never healthy. The same applies with sunlight as well, and it is already known that chronic exposure to ultraviolet or UV radiation present in sunlight is responsible for nonmelanoma skin cancer. There are two types of UV rays, classified as UVA rays and UVB rays. UVB rays are shorter rays that can lead to sunburn if exposed too much to it, however UVA rays are the longest rays and have the ability to travel more deepy into the skin.
Some effects of UVA rays on the skin includes skin aging and skin cancer, as they pass through window glass and are also produced by lamps and tools such as tanning booths. A tan induced by UVA, such as through tanning bed use, offers 5-10 times lower protection against sunburn from subsequent UV exposure compared to a tan induced by UVB. This is likely attributed to the less noticeable thickening of the epidermis and hyperkeratosis associated with a UVA-induced tan. This way, there is more exposure to it from people and as a result they are more prone to develop disease. UVA rays suppress the immune system which affects the primary and memory T cell function and are also constant throughout the day and year. UVB rays can also lead to skin aging and cancer and are responsible for most skin damage. They are more intense in the summer, midday, higher altitudes, and are closer to the equator.
Skin cancer is the most common form of cancer in the U.S. and basal cell carcinoma (BCC) is the most common form of skin cancer. Basal cell carcinoma typically manifests in areas exposed to sunlight, including the face, scalp, ears, chest, back, and legs. These tumors can exhibit various forms, with the prevalent presentation being a small, dome-shaped bump displaying a pearly white color. Another frequently observed indication is a recurring sore that bleeds, heals, and reappears. An estimated 3.6 million cases of BCC are diagnosed in the U.S. each year. More people are diagnosed with skin cancer each year in the U.S. than all other cancers combined. 1 in 5 Americans will develop skin cancer by the age of 70. The U.S. witnesses over two skin cancer-related deaths every hour. Having five or more sunburns doubles the likelihood of developing melanoma. If melanoma is identified early, the 5-year survival rate is as high as 99%.
The International Agency for Research on Cancer, an affiliate of the World Health Organization, includes ultraviolet (UV) tanning devices in its Group 1, a list of agents that are cancer-causing to humans. Group 1 also includes agents such as plutonium, cigarettes and solar UV radiation. Some risk factors aside from chronic UV expsure includes light complexion, light eyes, blonde or red hair, many freckles, tanning poorly and sunburning easily, many moles, genetics, blistering sunburns.
Prevention of skin cancer includes protecting oneself from UV rays by avoiding tanning beds and blocking them using sunscreen or protecting clothing. Sunscreen contains SPF which stands for Sun Protective Factor and broad spectrum SPF covers both UVA and UVB rays.
Some sun is never a bad thing. The exposure of sun to the skin helps to produce vitamin D, which helps calcium absorption for stronger and healthier bones. However, when you get constant exposure to the sun without any protection ultraviolet (UV) sun rays can cause major damage to the skin. This damage can vary from early aging, wrinkles, scarring all the way to cancer.
Ultraviolet (UV) radiation is energy from the some that makes it to the earth. It is a form of electromagnetic radiation. Although there are three types of UV radiation, the earth only received UVB and UVA. UVA rays have the least energy so damage to the skin usually includes wrinkles and aging. However, it can indirectly damage cells DNA. UVB rays are much more powerful than UVA, this type of radiation exposure causes direct cell DNA damage to the skin. UVB causes sunburns and skin cancer. The sun mostly emits UVB and that is the main source of this type of radiation. Ultraviolet radiation is most prominent during the middle of the day when the Sun is at its highest. UV radiation is also more common during the hot months of the year like Spring and Summer.
Protection against UV radiation important to avoid any of the unwanted side effects that are very harmful to a person. We protect against these UV rays using sunscreen, proper clothing, and avoidance of the sun in excess. There are two types of sunscreens, chemical sunscreens, or mineral sunscreens. Both are sold in drug stores over the counter and are effective in the protection against UV rays. Mineral sunscreen is also known as physical sunscreen. The main ingredients for these sunscreens include zinc oxide or titanium dioxide. These drugs reflect and scatter harmful rays from the sun. Mineral sunscreen is seen usually as thick and white, they take a minute to rub into the skin to get it evenly coated. These types of sunscreens should be placed on the skin at least 15 minutes before sun exposure to ensure maximum efficacy. Overall, mineral sunscreen is preferred for people with lighter skin due to the white cast and drier skin types.
Chemical sunscreens protect against both UVA and UVB rays, however some variations and ingredients are questionable in covering UVA rays. The active ingredients in these kinds of sunscreens include avobenzone, octinoxate and oxybenzone. Chemical sunscreens absorb into the skin and then absorbs UV rays converts the rays into heat and releases them from the body. This type of sunscreen doesn’t need to be applied 15 minutes before sun exposure it works on direct contact to skin. These types of sunscreens apply more evenly and often do not leave a white cast on the skin. Chemical sunscreens tend to be more sweat resistant that mineral sunscreens.
Overall, both sunscreen types are effective in the protection of UV rays and preventing unwanted harm to the skin. Both should always be reapplied throughout the day to get the maximum effect of the product. Something so simple as applying sunscreen daily can having life changing effects for people in the long run. Skin cancer is so common and often it is caught when at the deeper stages, making it harder to treat.
References:
Sander, Megan et al. “The efficacy and safety of sunscreen use for the prevention of skin cancer.” CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne vol. 192,50 (2020): E1802-E1808. doi:10.1503/cmaj.201085
Solid organ transplantation has revolutionized the treatment of end-stage organ failure, promoting the survival and quality of life of patients. However, solid organ transplant recipients (OTRs) face an increased risk of developing skin cancer, compared to the general population. The increased susceptibility is primarily attributed to the long-term immunosuppressive therapy required to prevent organ rejection which impairs the immune system’s ability to monitor for atypical cells. OTRs have a 65-250-fold and 6-16-fold greater risk of developing cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) than the general population, respectively; other cancers such as melanoma, Merkel cell carcinoma and Kaposi sarcoma are also more common in OTRs, but less likely than SCC (and BCC).
The pathways related to cutaneous malignancy in OTRs are not fully understood but it is generally accepted that immunosuppressive agents play a major role. As previously mentioned, immunosuppression results in reduced immune surveillance, leading to increased survival and proliferation of atypical cells. Immunosuppressive medications – especially azathioprine and cyclosporine – have been linked to the development of skin cancer in multiple trials. Azathioprine has been associated with mutagenic effects following UV radiation-exposure, while cyclosporine has been associated with changes in cell morphology and inhibition of DNA repair. Furthermore, immunosuppression allows for proliferation of oncogenic viruses such as Epstein-Barr virus, human papillomavirus, Kaposi sarcoma herpes virus, and Merkel cell polyomavirus which are associated with the development of cancer in these patients. Several risk factors also contribute to the elevated incidence of skin cancer in OTRs. A large cohort of >10,000 solid OTRs showed that 8% of patients evaluated developed a post-transplant skin cancer. The main predictors of skin cancer included: pre-transplant skin cancer (hazard ratio [HR] 4.69, 95% CI 3.61-6.09), male sex (HR 1.61, 95% CI 1.34-1.89), thoracic organ transplant (heart or lung) (HR 1.51, 95% CI 1.26-1.82), white race (HR 7.79, 95% CI 5.34-11.37), and ≥50 years at time of transplantation (HR 2.65, 95% CI 2.12-3.21). Other notable risk factors include past overexposure to UV radiation and history of transplant rejection. OTRs are also at an increased risk of additional lesions following SCC or BCC development; one study found the cumulative incidence of a second SCC was 44%, 67% and 76% after 1, 3 and 5 years, respectively.
The clinical manifestations of skin cancer in OTRs typically resemble those seen in the general population but may develop in unusual sites or exhibit atypical features (more often with SCC than BCC). Additionally, OTRs often present with multiple, more aggressive tumors, necessitating a high index of suspicion. Preventive measures play a pivotal role in mitigating the risk of skin cancer development and increased mortality in OTRs, requiring close collaboration with dermatologists and the transplant team. Prior to and following transplantation, OTRs should be educated on the importance of sun protection. The use of daily broad-spectrum sunscreen, sun-protective clothing, and avoidance of excessive sun exposure (especially during peak hours) should be emphasized. OTRs should be instructed to perform monthly skin self-examinations and report any suspicious lesions immediately; the American Academy of Dermatology provides online tutorials for patients to refer to. Since the intensity and duration of immunosuppressive regimens promotes the development of cutaneous malignancies in OTRs, reduction of immunosuppression may be considered in patients with multiple lesions, recurrent or metastatic disease. However, there is insufficient evidence evaluating the effects of immunosuppression reduction and reduction may increase the risk of organ rejection; thus, the risks and benefits must be carefully considered. If medically feasible, some studies have shown that mTOR inhibitors (such as sirolimus and everolimus) or mycophenolate mofetil are associated with a lower incidence of skin cancer than azathioprine and may be a safer option for OTRs than immunosuppression reduction.
The importance of sunscreen is well-established in evidence-based medicine. Sunscreen helps protect the skin from the harmful effects of ultraviolet (UV) radiation from the sun, and its benefits are supported by extensive scientific research. Skin cancer, including melanoma, basal cell carcinoma, and squamous cell carcinoma, is strongly linked to UV radiation exposure from the sun. Multiple studies have shown that regular sunscreen use can significantly reduce the risk of skin cancer. For example, a study published in the Journal of Clinical Oncology in 2011 found that daily sunscreen use reduced the risk of melanoma by 50-73% compared to infrequent use.
A common visual of sun damage is sunburn. Many people experience sunburn due to being in UV rays for long periods of time and not having their skin properly protected. Sunburn is not only painful but also a clear indication of skin damage from UV radiation. Clinical studies have demonstrated that applying sunscreen with a high sun protection factor (SPF) can effectively prevent sunburn and reduce the immediate damage caused by UV exposure. Chronic sun exposure can lead to premature aging of the skin, including wrinkles, fine lines, and age spots. Evidence-based research has shown that sunscreen use helps prevent and delay the signs of premature skin aging, keeping the skin looking younger and healthier.
UV radiation can cause DNA damage and oxidative stress in the skin, leading to various skin conditions and disorders. One major consequence of DNA damage to the skin cells from UV radiation is unfortunately skin cancer. Studies have indicated that sunscreen can help mitigate this damage by reducing the harmful effects of UV radiation on the skin's cells and structures.
Some individuals suffer from photosensitive skin conditions (photodermatoses) that can be aggravated by UV exposure. Photosensitivity is also a possible side effect from certain medications. When taking certain drugs such as NSAIDs, sulfonylureas, antihistamines and others, it should be noted that photosensitivity is a possibility and to use protection. Sunscreen is an essential part of managing these conditions, as it provides a physical barrier against UV radiation. After certain skin procedures, such as chemical peels, laser treatments, or surgery, the skin is highly sensitive and vulnerable to UV damage. Dermatologists often recommend the use of sunscreen to protect the healing skin and minimize the risk of complications.
Evidence from a variety of sources underscores the critical role of sunscreen in protecting the skin from the detrimental effects of ultraviolet radiation from the sun. Notably, both observational studies and large-scale randomized controlled trials (RCTs) have consistently supported the effectiveness of sunscreen in preventing signs of photoaging, such as wrinkles, telangiectasia, and pigmentary alterations induced by UV radiation. These findings emphasize the cosmetic and aesthetic benefits of sunscreen use in maintaining youthful and healthy skin.
Evidence from multiple studies and randomized controlled trials strongly suggests that sunscreen plays a pivotal role in preventing skin cancer, particularly squamous cell carcinomas. Experimental studies conducted in the 1980s and 1990s demonstrated that sunscreens can shield against cell damage consistent with carcinogenesis in animal models. Importantly, a well-conducted, community-based RCT involving adult Australians revealed a substantial 40% reduction in the incidence of squamous cell carcinomas among participants who used sunscreen daily as recommended, compared to those who used it less frequently. Although the incidence of basal cell carcinomas did not significantly decrease, this can be attributed to the protracted development of these tumors.
The long-term benefits of sunscreen use are evident in reduced risks of invasive melanoma, even many years after the study's completion. Additionally, sunscreen has been shown to halt signs of skin aging caused by photodamage, emphasizing its role in preserving skin health and appearance over time. In organ transplant recipients, a high-risk population for skin cancer, the regular use of sunscreen, particularly with a high SPF rating, led to a notable reduction in the development of actinic keratoses and various types of skin carcinomas.
While recent meta-analyses have raised some questions regarding the efficacy of sunscreen in preventing skin cancer, it is important to consider that these analyses included studies with varying methodologies and sunscreen formulations. Nevertheless, the highest-quality evidence available, including well-designed RCTs and experimental studies, collectively demonstrates that sunscreen is a valuable tool in reducing the risk of skin cancer and maintaining skin health. As such, sunscreen remains a recommended and evidence-based measure for safeguarding skin from the harmful effects of UV radiation.
Sunscreen is an integral component of maintaining overall skin health and preventing a wide range of skin problems associated with UV radiation exposure. The importance of sunscreen in evidence-based medicine is well-documented. Regular and proper use of sunscreen is a proven strategy to reduce the risk of skin cancer, prevent sunburn, delay premature aging, and protect the skin from UV-induced damage. Dermatologists and health organizations worldwide recommend sunscreen as a crucial part of a comprehensive sun protection strategy to promote skin health.
References:
Henderson, S. I., King, K. L., Karipidis, K. K., Tinker, R. A., & Green, A. C. (2022). Effectiveness, compliance and application of sunscreen for solar ultraviolet radiation protection in Australia. Public health research & practice, 32(1), 3212205. https://doi.org/10.17061/phrp3212205
Sander, M., Sander, M., Burbidge, T., & Beecker, J. (2020). The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne, 192(50), E1802–E1808. https://doi.org/10.1503/cmaj.201085
Skin cancer is one of the most prevalent cancers in the United States. The main risk factor is ultraviolet (UV) radiation exposure from the sun. Sunscreen is made to protect the skin against these harmful UV rays, thus reducing one’s risk of skin cancer. There are three different types of UV rays including UVA, UVB, and UVC. The two rays that can penetrate the earth's atmosphere are UVA and UVB. Therefore, they can reach the skin and cause mutations in the individual's DNA leading to skin cancer. Sunscreen’s purpose is to block both of these UV rays by either absorbing or reflecting them. Chemical sunscreens have organic compounds that absorb the rays, while physical sunscreens contain zinc oxide or titanium dioxide that reflects the UV rays.
UVB rays cause sunburn and are also the main cause of non-melanoma cancers such as basal cell carcinoma and squamous cell carcinoma. Sunscreen is classified by chemical or physical as well as, the sun protection factor (SPF). The SPF indicates what level of protection one will receive from UVB rays. For example, SPF 30 can protect against about 97% of UVB rays. There is no sunscreen that will give 100% protection however, it is still important to wear it. UVA rays, on the other hand, are involved in skin aging and some skin cancer. They are able to penetrate the skin deeper thus, causing damage to elastin and collagen which can lead to premature wrinkles. There are sunscreens available that can protect against both kinds of UV rays called broadspectrum. For sunscreen to protect the skin effectively, it must be applied correctly and in timely intervals. It is recommended to apply sunscreen about 15-30 minutes before being exposed to the sun and every 2 hours while outside.
Multiple studies have demonstrated the effectiveness of sunscreen in reducing the risk of skin cancer. A systematic review and meta-analysis published in the Journal of Clinical Oncology in 2018 analyzed data from 19 studies and found that regular sunscreen use was associated with a significant reduction in the risk of melanoma, the most deadly form of skin cancer. Another study published in the Journal of the American Academy of Dermatology in 2019 showed that daily sunscreen use led to a 50% reduction in the incidence of melanoma, squamous cell carcinoma, and basal cell carcinoma combined.
References:
Hung M, Beazer IR, Su S, Bounsanga J, Hon ES, Lipsky MS. An Exploration of the Use and Impact of Preventive Measures on Skin Cancer. Healthcare (Basel). 2022 Apr 15;10(4):743. doi: 10.3390/healthcare10040743. PMID: 35455920; PMCID: PMC9025621.
Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020 Dec 14;192(50):E1802-E1808. doi: 10.1503/cmaj.201085. PMID: 33318091; PMCID: PMC7759112.
Sunscreen is an important part of our day-to-day lives as it is one of the best and easiest ways to protect the skin from the sun’s rays. These rays, ultraviolet have subtypes A and B, both of which cause radiation to reach us. While we do get vitamin D from the sun, there is also the risk of serious health issues, such as cancer. According to the CDC, “Skin cancer is the most common cancer in the United States. The two most common types of skin cancer are basal cell cancer and squamous cell cancer. Typically, they form on the head, face, neck, hands, and arms because these body parts are the most exposed to UV radiation. Most cases of melanoma, the deadliest kind of skin cancer, are caused by exposure to UV radiation.” People at risk for these are typically those with lighter hair/skin color, who spend a lot of time in the sun, and even those who take products that may cause photosensitivity, such as antibiotics and birth control pills.
There are 2 different types of sunscreens on the market. The more common one, mineral sunscreen, is usually made from either zinc oxide or titanium oxide, or both. Chemical sunscreens, on the other hand, contain oxybenzone, avobenzone, and/or octocrylene. Although they do the same job, they act differently which may impact what we should recommend to a patient seeking advice. Mineral sunscreen act on UV reflection while chemical sunscreens work on UV absorption. These characteristics affect the stability of the product. Mineral sunscreen is more efficient and stable, while chemical sunscreen can break down more easily. It’s also worth noting that chemical sunscreens can have interactions with other chemicals. An important one to note is oxybenzone and chlorine, commonly found in pools. When comparing their ability to effectively protect against radiation, it is seen that mineral sunscreens are typically available at lower SPF when compared to chemical sunscreens. Additionally, it is noticed by consumers that mineral sunscreen is more prone to leaving a chalky appearance on the skin, which may not be admirable. Chemical sunscreens are more likely to blend into the skin and make it look like there is no product there.
With the summer months coming, we get a lot of patients coming in and asking us which sunscreen is recommended and which is better for protection against the sun. As of right now, I feel that the differences are slightly above negligible. Both options help protect against UVB radiation. Something to consider is what occasion the patient is using the sunscreen for. If they are going to the beach or the pool, then maybe they should stick with a mineral sunscreen, in case the chemicals in the chemical sunscreen react with something in the water. If they want to use it for day-to-day protection, then maybe a chemical sunscreen would be better since it has a more natural finish than minerals. Recently, there have been products that have come out with a combination of mineral and chemical sunscreen in one product, but it is unclear which is better when compared to its isolated counterparts
Resources
Varedi, A., Wu, Y. P., Klein, S. Z., Leachman, S. A., & Grossman, D. (2019). Mineral sunscreens not recommended by Consumer Reports: Suggestions to improve the review process. Journal of the American Academy of Dermatology, 80(3), 832–833. https://doi.org/10.1016/j.jaad.2018.09.009
“UV Radiation.” Centers for Disease Control and Prevention, 5 July 2022, www.cdc.gov/nceh/features/uv-radiation-safety/index.html#:~:text=UV%20radiation%20is%20classified%20into,some%20UVB%20radiation%20reaches%20earth.
Ultra violet (UV) radiation is a form of electromagnetic radiation that naturally is emitted from the sun. There are three different types of UV radiation: UVA, UVB, and UVC. UVA rays have the least energy but can cause skin cells to age and can cause indirect damage to cells’ DNA. UVA is linked to long-term skin damage like wrinkles. UVB rays have more energy than UVA rays and can directly damage cells’ DNA. These rays are the main cause of sunburn and cause the most skin cancers. UVC rays have the highest energy of the three but they do not pose a risk to humans due to the fact that they react with ozone in the atmosphere before they are able to reach the ground. Sunlight is the main way that humans are exposed to UV radiation although there are some manmade mechanisms such as tanning beds and welding torches. UVA and UVB rays are not equally emitted by the sun. about 95% of the UV rays are UVB while 5% are UVA. The strength of the rays reaching humans varies according to several different factors. UV rays are strongest midday (10am-4pm) as well as during the spring and summer seasons. Exposure to UV radiation decreases as your location gets farther from the equator. UV radiation exposure may also be increased in areas with water, sand, snow, or pavement due to the rays’ ability to bounce off these surfaces (American Cancer Society).
There are three main types of skin cancer that can be caused by UV radiation: basal cell carcinoma, squamous cell carcinoma, and melanoma. These three types vary in their origin, severity, and treatment. Basal cell carcinoma (BCC) is the most common type of skin cancer. It originates in the basal cells of the skin and looks like a flesh-colored round growth, pearl-like bump, or a pinkish patch of skin. This type is common on the head, neck, and arms. Squamous cell carcinoma (SCC) is the second most common type of skin cancer and looks like a red firm bump scaly patch, or a sore than heals and then reopens. This type tends to form on skin that gets the most sun exposure like the rim of the ear, face, neck, arms, chest, and back. Melanoma is the most serious type of skin cancer with the highest tendency to spread to other tissues. It can develop within a mole already present on the skin or appear as a dark spot. Each of these types of skin cancer occur at a higher rate in people with lighter complexions (American Academy of Dermatology).
Treatment of basal cell carcinoma involves standard surgical excision as first-line treatment. Curettage and electrodesiccation is an alternative first-line option in which the affected skin is scraped off. Similar to BCC, SCC also involves standard surgical excision as a first-line treatment option. Mohs surgery which is a specialized tissue-sparing procedure is also an option for SCC. Melanoma is usually treated by removing the affected cells by wide excision. Wide excision of melanoma is generally performed down to the muscle fascia unlike the excision used for BCC or SCC. Depending on whether or not the melanoma has spread, treatment may include more invasive therapy (Gershenwald). While the surgical removal of skin cancer is a viable treatment option, it is still best to prevent skin cancer from occurring in the first place by staying out of the sun at an early age or wearing protective clothing when being in the sun is unavoidable.
Resources:
Gershenwald J, Keung E. Surgical management of primary cutaneous melanoma. UpToDate. https://www.uptodate.com/contents/surgical-management-of-primary-cutaneous-melanoma-or-melanoma-at-other-unusual-sites?search=treatment+of+melanoma&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2#H1701593750. Accessed March 15, 2022.
Skin cancer: Types and treatment. American Academy of Dermatology. https://www.aad.org/public/diseases/skin-cancer/types. Accessed March 15, 2022.
Ultraviolet (UV) radiation. American Cancer Society. https://www.cancer.org/cancer/cancer-causes/radiation-exposure/uv-radiation.html#:~:text=UV%20rays%2C%20either%20from%20the,actinic%20keratosis%2C%20and%20solar%20elastosis. Published July 10, 2019. Accessed March 15, 2022.
The sun is the skin’s worst enemy. Sun exposure can lead to sunburns which increases the risk of skin cancer. Skin cancer starts when abnormal cells in the epidermis are growing out of control. The main types of skin cancer are basal cell carcinoma, squamous cell carcinoma and melanoma. Basal cell carcinoma is the most common form of skin cancer, and is caused by a combination of intermittent, intense exposure and cumulative, long-term exposure to UV radiation from the sun. It usually develops on skin areas typically exposed to the sun such as the face, ears, neck, scalp, shoulders and back. Squamous cell carcinoma is the second most common form of skin cancer, and is caused by cumulative, long-term exposure to UV radiation from the sun and tanning beds. It usually develops on sun-exposed areas. Melanoma is the most dangerous form of skin cancer, and it is estimated that there will be 197,700 new cases in the U.S. in 2022. It is caused by intense, intermittent sun exposure and tanning beds. It can be found anywhere on the body, even in areas that are not typically exposed to the sun.
The use of sunscreen can reduce the danger posed by UV radiation. UV radiation is part of the natural energy produced by the sun, and there are two types of UV light that contribute to the risk of skin cancer. UVA accounts for 95% of UV radiation that reaches the Earth’s surface with fairly constant intensity over the day. It penetrates the ozone, clouds, and window glass. It also penetrates the human skin more deeply and is associated with skin aging. UVB, on the other hand, accounts for 5% of the UV radiation that reaches the Earth’s surface with varied intensity that peaks around midday. It is partially absorbed by the ozone and clouds and does not penetrate window glass. It is not absorbed as deeply into the skin and is associated with skin burning. UVA is connected to the “broad-spectrum protection” and UVB is connected to the Sun Protection Factor (SPF) on sunscreen product labels. SPF indicates how long the sun’s radiation would take to redden your skin with sunscreen compared to without sunscreen.
There are two types of sunscreen: physical (mineral) and chemical. Physical sunscreen has ingredients like titanium dioxide and zinc oxide, and they block and scatter UV rays before it penetrates the skin. Chemical sunscreen has ingredients like oxybenzone, avobenzone, octocrylene and ecamsule, and they absorb UV rays before it damages the skin. Physical sunscreens may cause less skin irritation than chemical sunscreens, but both are tested as safe and effective.
Everyone over the age of 6 months should be using sunscreen daily that is broad spectrum with an SPF 15 or higher. It is found that using SPF 15 sunscreen daily can reduce the risk of developing squamous cell carcinoma by about 40 percent. SPF 15 is ideal for daily use, but SPF 30 or higher is necessary for extended outdoor activities. No matter the SPF, sunscreen should be applied 30 minutes before going outside and reapplied every two hours and immediately after swimming or sweating. It is necessary to apply sunscreen daily, even when it is cloudy because up to 80 percent of UV radiation reaches the earth. Sunscreen application should not be limited only to the face, but also to the entire body.
Sunscreen alone isn’t enough, going under the shade and wearing sun-safe clothing, a wide-brimmed hat and UV blocking sunglasses are also important.
References:
1. Green AC, Williams GM. Point: sunscreen use is a safe and effective approach to skin cancer prevention. Cancer Epidemiol Biomarkers Prev. 2007;16(10):1921-1922. doi:10.1158/1055-9965.EPI-07-0477
2. Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020;192(50):E1802-E1808. doi:10.1503/cmaj.201085
3. “Skin Cancer Information.” The Skin Cancer Foundation, 20 Jan. 2022, https://www.skincancer.org/skin-cancer-information/.
4. “Sunscreen.” The Skin Cancer Foundation, 28 Jan. 2022, https://www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/.
5. “UV Radiation.” The Skin Cancer Foundation, 28 Jan. 2022, https://www.skincancer.org/risk-factors/uv-radiation/.
Melanoma is the most serious form of skin cancer due to its ability to quickly spread to other organs if not detected at an early stage. This type of skin cancer isn’t discussed as much as carcinomas because it isn’t as common. Melanomas make up less than five percent of all skin cancers.
Melanoma occurs when there is DNA damage due to ultraviolet radiation that triggers mutation sin melanocytes. Melanocytes are skin cells that produce melanin when the skin is exposed to IV radiation. Treatment for melanoma varies throughout the different stages. In the early stages, it can be treated with surgery where the melanoma is removed. Towards the later stages, an attempt to remove the melanoma can be made along with targeted drug therapy and use of immunotherapy. The immunotherapy drugs are called checkpoint inhibitors such as pembrolizumab and nivolumab. These drugs are generally the first drugs used because they have the capability to shrink tumors in certain patients for long periods of time.
Ipilimumab is another checkpoint inhibitor that is usually not a drug used as first line treatment. It sometimes be used in combination with pembrolizumab or nivolumab. Due to the risk of serious side effects, this combination should be carefully considered.
The New England Journal of Medicine has an article based on a study comparing the efficacy of ipilimumab and nivolumab combination compared to the drugs being used alone in melanoma. In this study, the primary endpoints were progression-free survival and overall survival between the groups. There were three study groups comprised of 945 patients with previously untreated advanced melanoma were randomized 1:1:1 to receive nivolumab plus ipilimumab, nivolumab plus placebo, and ipilimumab plus placebo. All the patients in this study had unresectable or metastatic histologically confirmed stage III or stage IV melanoma. The efficacy endpoints were based on the intention-to-treat population. At 60 months, they followed up to assess overall survival, progression-free survival, and the objective response rate at the 95% CI were performed. They found that overall survival was longer in the two nivolumab containing groups compared to the ipilimumab group. The overall survival at 5 years was 52% in the combination group, 44% in the nivolumab group, and 26% in the ipilimumab group. The median progression-free survival was 11.5 months in the combination group, 6.9 months in the nivolumab group, and 2.9 months in the ipilimumab group. In terms of safety, the combination group had the highest adverse event occurrence at 59%. 23% of the patients in the nivolumab group reported side effects. 28% of patients in the ipilimumab group reported side effects. Based on the results of this study, it was found that patients taking both ipilimumab and nivolumab had sustained long-term overall survival at 5 years as compared to patients taking only ipilimumab and only nivolumab. This study probably helped progress the guidelines in using these immunotherapy drugs in the treatment of melanoma. Now, it is possible to see ipilimumab and nivolumab be used in the same treatment regimen for melanoma. The study also confirmed the worse safety profile in the combination group compared to using the drugs individually, which should be carefully taken into consideration when treating melanoma.
References:
1. Larkin J, Chiarion-Sileni V, Gonzalez R, Grob JJ, Rutkowski P, Lao CD, Cowey CL, Schadendorf D, Wagstaff J, Dummer R, Ferrucci PF, Smylie M, Hogg D, Hill A, Márquez-Rodas I, Haanen J, Guidoboni M, Maio M, Schöffski P, Carlino MS, Lebbé C, McArthur G, Ascierto PA, Daniels GA, Long GV, Bastholt L, Rizzo JI, Balogh A, Moshyk A, Hodi FS, Wolchok JD. Five-Year Survival with Combined Nivolumab and Ipilimumab in Advanced Melanoma. N Engl J Med. 2019 Oct 17;381(16):1535-1546. doi: 10.1056/NEJMoa1910836. Epub 2019 Sep 28. PMID: 31562797.
2. “Treatment of Melanoma by Stage.” American Cancer Society, https://www.cancer.org/cancer/melanoma-skin-cancer/treating/by-stage.html.
Cutaneous squamous-cell carcinoma (CSCC) continues to be the second most prominent skin cancer in the world, second only to basal-cell carcinoma. Many skin cancers can go undetected for years, allowing it to spread without notice and become more deadly than if caught early. The cancer becomes metastatic, spreading to different parts of the body and may no longer be susceptible to surgery or chemotherapy. Immunotherapy is an area of cancer treatment that has been more frequently used in patients in whom surgery or radiation therapy are no longer options. In many treatment regimens, we can see immunotherapy as first-line, adjunct to other therapies, or used alone when there are not many options left. An important aspect of immunotherapy is ensuring that the drug of choice will influence the tumor. Tumors become highly mutated as they grow in the body, and skin tumors even more so because of the exposure to chronic ultraviolet light. These highly mutated tumors will likely show a positive response to immunotherapy that have a checkpoint inhibition.
Cemiplimab is a monoclonal antibody that is targeted against immuno-checkpoint programmed cell death-1 (PD-1) receptors that are expressed on tumors. Its ligand, PD-L1, is expressed on antigen presenting cells, mesenchymal stem calls, mast cells, and other cells of the host immune system. PD-L1 is also expressed on tumor cells. Tumor cells that have a higher expression of PD-L1 suppress signaling pathways that are involved in T-cell activation, which allows the tumor to evade death by the host immune system. Immunotherapies that target this PD-1/PD-L1 pathway have been shown to have better therapeutic effects on tumors that express this immune checkpoint.
Before the approval of cemiplimab, there were no systemic therapies available to treat advanced cutaneous squamous cell carcinoma. Approval of cemiplimab was based on two clinical trials that assessed a durable objective response rate from a multi-center, dose-finding trial, on patients with different types of advanced tumors. Patients were enrolled in the trial regardless of prior treatment, but only if surgery or radiation were no longer recommended. The objective response rate (ORR) evaluated using the Response Evaluation Criteria in Solid Tumors (RECIST) criteria and an additional assessment using digital photography for patients with locally advanced tumors were used. Results of the studies show that among 108 patients with advanced disease (75 with metastatic disease and 33 with locally advanced) disease, the ORR was 47% (95% CI: 38, 57) with 4% complete and 44% partial response rates. For the 75 patients with metastatic disease, the ORR was 47% (95% CI: 35, 59) and 49% (95% CI: 31, 67) for the 33 with locally advanced disease.
Like most immunotherapy, the safety data includes serious immune mediated adverse reactions including pneumonitis, hepatitis, colitis, diabetes mellitus, and nephritis. Among patients with advanced cutaneous squamous cell carcinoma, cemiplimab produced a positive response in about half of the patients with a similar safety profile to other immunotherapy the work with the PD-1/PD-L1 pathway. Since its initial approval in 2018, the indications for cemiplimab have been expanded to include basal cell carcinoma and non-small cell lung cancer.
References:
1. Ahmed SR, Petersen E, Patel R, Migden MR. Cemiplimab-rwlc as first and only treatment for advanced cutaneous squamous cell carcinoma. Expert Rev Clin Pharmacol. 2019;12(10):947-951. doi:10.1080/17512433.2019.1665026
2. Zheng Y, Fang YC, Li J. PD-L1 expression levels on tumor cells affect their immunosuppressive activity. Oncol Lett. 2019;18(5):5399-5407. doi:10.3892/ol.2019.10903
3. Center for Drug Evaluation and Research. Cemiplimab-RWLC for cutaneous squamous cell carcinoma. U.S. Food and Drug Administration. https://www.fda.gov/drugs/drug-approvals-and-databases/fda-approves-cemiplimab-rwlc-metastatic-or-locally-advanced-cutaneous-squamous-cell-carcinoma. Accessed January 19, 2022.
Sunscreen has always been a recommended product to be used on individuals on a daily basis. Even when individuals do not plan to be outside, it is still recommended to wear sunscreen indoors. This is because UV rays can still emit indoors too, like at any openings such as a window. Health care providers over the years have promoted the use of sunscreen as it can cause serious health damages and conditions. Although sunlight is very vital for any individuals, it is also as important to wear sunscreen as well. Since, it is possible for any kind of sun rays to cause serious skin damages, such as skin cancer, due to the ultraviolet radiation of the sun.
UV rays can cause damaging effects on DNA. The association between UV rays and DNA is that UV rays can cause changes in the skin which causes actinic keratoses, a precursor of non-melanoma skin cancer (NMSC) and squamous cell carcinoma (SCC). It is said that NMSC is the most common type of malignancy in the United States. UV rays are categorized by either UVA and UVB, and while both types of UV rays are of concern, more attention is placed on UVA. NMSC and SCC are generally attributed to UVA radiation because UVA penetrates through the skin deeper than UVB. However, other factors including amount of sun exposure during childhood, genetic predisposition, pigmentation, and aging contribute to the risk for developing skin cancer.
To briefly explain the mechanism of UV rays that cause damage, UVA radiation exposure causes the formation of reactive oxygen species. The reactive oxygen species then damages DNA by breaking the tertiary structure of DNA. UVB is absorbed by DNA to cause similar structural damage. Furthermore, mutations in p53 tumor suppressor gene which is involved with DNA repair and apoptosis in cells with sustained DNA damage caused by UV ray exposure is associated with DNA damaging and skin malignancy development.
There are many sunscreens on the market. So, how do individuals know which to choose from? Sunscreen efficacy is based on a factor called the sun protection factor, or as most people know, SPF. For a long time, researchers and scientists have known that sunscreen is effective and beneficial to use. However, there is still an ongoing debate on what the precise SPF value is the absolute best to use. Nevertheless, the recommended range for SPF value is anywhere from 15 to 30, that studies have shown.
Studies have found that SPF only refers to the ability to protect the skin against sunburn and is unrelated to reducing the risk for skin cancer. Sunburn is caused by the skin’s exposure to sunlight, in particular, UVB. Therefore, the SPF portion of sunscreen is only meant for skin protection against sunburn and not the risk of developing skin cancer from UVA and UVB. Furthermore, SPF does not include protection against UVA. A study conducted by Poon and colleagues has demonstrated that immune protection factor or IPF was a better predictor of protection against UVA than SPF. Nevertheless, general studies all agree that broad spectrum sunscreens can decrease the rate of new precancerous lesions, which leads to less actinic keratoses and therefore fewer SCC. Unfortunately, there is little evidence of sunscreens protecting against basal cell skin cancers and melanomas.
In regard to application of the products, some scientists have argued that the sunscreen should be reapplied every 2 to 3 hours after the initial application. However, studies done by Diffey, et. al shows that “typically reapplication of sunscreen at 20 minutes results in 60% to 85% of the UV exposure if sunscreen were reapplied at 2 hours.” So, in conclusion, Diffey states that sunscreen should be first applied 15 to 30 minutes before going outside in any areas of the body that may be exposed to the sunlight. Then, to repeat the application again, after 15 to 30 minutes. And of course, after that any reapplication should be considered depending on what the individual may be doing or how long the individual is outside in the sun for.
Overall, there is still ongoing talk and research about the best SPF reapplication time period is between numerous researchers. Nevertheless, if there is one thing that all researchers, scientists, and providers can all agree on, it is that every individual should wear sunscreen every single day, no matter what their day may look like.
References:
Diffey, B. L. (2001). When should sunscreen be reapplied?. Journal of the American Academy of Dermatology, 45(6), 882-885.
Gasparro, F. P., Mitchnick, M., & Nash, J. F. (1998). A review of sunscreen safety and efficacy. Photochemistry and photobiology, 68(3), 243-256.
Raffa RB, Pergolizzi JV Jr, Taylor R Jr, Kitzen JM; NEMA Research Group. Sunscreen bans: Coral reefs and skin cancer. J Clin Pharm Ther. 2019 Feb;44(1):134-139. doi: 10.1111/jcpt.12778. Epub 2018 Nov 28. PMID: 30484882.
Our skin is the largest organ of our bodies, however, it is also one of the most sensitive as well. Our skin is directly affected by the environment unlike the other organs in our body.1 Skin cancer is one of the most prominent cancers in the United States. There are different types of skin cancers ranging from non-melanoma skin cancers to melanoma which is the most severe form. Skin cancer is on the rise, where approximately 5 million people a year are diagnosed with skin cancer, so it is important to protect ourselves from the disease.2 There are multiple different risk factors for skin cancer, but the most predominant would be UV radiation. Although our bodies need natural UV radiation as a source of vitamins, excessive exposure is seen to deteriorate our skin and make it more susceptible to cancer.
There are two different UV radiations that are seen to be associated with skin cancer, UVA and UVB. UVA is seen to cause skin aging due to its long wavelength, and is seen in the use of tanning beds, whereas UVB causes skin burning because of its shorter wavelength. UVA is more harmful than UVB due to its longer wavelength and reaches deeper into the skin layers.3 Although UV radiation is one of the main causes of skin cancer, it is also one of the most important modifiable risk factors, meaning that it is a risk that can be easily prevented if changed.4 In the epidermis, there are cells called melanocytes and they release a dark pigment, known as melanin, when the skin cells are damaged by UV. Melanin is able to absorb UV light, acting as a UV shield, but melanin isn't able to completely prevent skin damage from UVB. Essentially, the melanin can begin to absorb the UV light and cause damaging effects to the skin.5 Many people with darker skin tones believe that they are void of developing skin cancers, however, it is still very possible to develop skin cancer in both light and dark skin tones due to excessive UV exposure.
There are 3 major types of skin cancer: basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), which are both classified as non-melanoma skin cancer, and melanoma.6 Basal cell carcinoma usually develops in areas of the body that was exposed to the sun, such as the face, however, the cancer cells grow slowly making it unlikely to become life-threatening. Squamous cell carcinoma also usually occurs in sun-exposed areas of the body, such as the face and hands, however, this type is more likely to spread. Melanomas are the most aggressive type of skin cancer and can develop anywhere on the body. Melanomas can develop in existing benign moles that become cancerous and can be cured if detected and treated early. If left untreated, melanomas can eventually lead to death. Studies have shown a significant decrease in incidences of squamous cell carcinomas and a reduced risk in invasive melanomas in people who use sunscreen daily.7
It is important to protect our skin from the excessive harmful effects of UV radiation. Some ways to protect oneself is using sunscreen with a sun protective factor (SPF) of 15 or higher. It is important to learn how to read sunscreen labels to know which is properly protecting your skin and which is not. Sunscreens are categorized as physical and chemical blockers.8 Sunscreen can either absorb or reflect UV photons before they reach our skin. Sunscreens that are considered physical blockers are those that act as a shield and deflect UV rays away from the skin. It usually contains two active mineral ingredients: zinc oxide and titanium oxide, which are the only two ingredients that have been labeled safe by the FDA. Recently, certain sunscreen brands and products were recalled because they contain a harmful chemical known as benzene, which is found to be carcinogenic. According to Johnson & Johnson, benzenes are found in many of our daily exposures, but it is a potential cancer causing substance, also known as a human carcinogen, depending on the level and extent of exposure.9 The very product we use to protect our skin from the harmful UV rays to prevent skin cancers is seen to be the source of causing cancers. It is important to distinguish the proper sunscreens to use with the correct ingredients to protect you from all types of harm.
Physical sunscreens that protect against both UVB and UVA are also labeled broad-spectrum. Chemical sunscreens absorb the UV rays and convert them into heat which is then released. Chemical sunscreens are not as long lasting as physical sunscreens, therefore it has to be frequently applied throughout the day and takes longer to work ranging from 30 minutes to 50 minutes compared to physical sunscreens which come into action instantly. According to the American Academy of Dermatology, it is recommended to choose a sunscreen that protects against both UVA and UVB with an SPF of either 30 or 50 depending on the weather.10 The sun protective factor (SPF) is determined by calculating the number of seconds it takes for the skin to be exposed. For example, if it normally takes about 10 minutes in the sun for a person’s skin to get burned without sunscreen, then theoretically if they were to use SPF 30, the sunscreen should last them 50 times as long, about 500 minutes. Nevertheless, the sunscreen should still be applied frequently about every 2 hours. In addition to sunscreens, a person can use protective clothing, such as long sleeves and pants, hats, etc. to shield themselves from the UV light, as well as simply staying out of the sun, especially when the sun’s rays are strongest between 10 a.m. and 4 p.m.2 Although people love to tan and stay in the sun during the sunny summer days, they could use these methods to help protect themselves and lower their risk of developing skin cancer. Sunscreen does not stop a person from getting that glowing tan, but will protect them from absorbing the harmful UV rays.
Cancer doesn’t discriminate, so it is important to note that all types of people can develop skin cancer due to excessive sun exposure, and we all need to protect ourselves from it. Furthermore, our body is delicate and it is important to protect ourselves from different forms of harm, such as chemicals as well as environmental conditions. As pharmacists, we need to educate the public on proper sun exposure and how to protect ourselves. Certain things like sunscreens are important to note and help a consumer read a label to ensure they are receiving the correct protection, as well as free of any other harmful chemicals, such as benzene. The sun may be our friend, but it can always turn on us. Skin-aging and non-melanoma skin cancers are largely preventable and it is our priority to help the world as a whole to educate on sun safety and protection.
References:
1 Rittié L, Fisher GJ. Natural and sun-induced aging of human skin. Cold Spring Harb Perspect Med. 2015;5(1):a015370. Published 2015 Jan 5. doi:10.1101/cshperspect.a015370
2 Watson M, Holman DM, Maguire-Eisen M. Ultraviolet Radiation Exposure and Its Impact on Skin Cancer Risk. Semin Oncol Nurs. 2016;32(3):241-254. doi:10.1016/j.soncn.2016.05.005
5Brenner M, Hearing VJ. The protective role of melanin against UV damage in human skin. Photochem Photobiol. 2008;84(3):539-549. doi:10.1111/j.1751-1097.2007.00226.x
6Nakayama K. Growth and progression of melanoma and non-melanoma skin cancers regulated by ubiquitination. Pigment Cell Melanoma Res. 2010;23(3):338-351. doi:10.1111/j.1755-148X.2010.00692.x
7 Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020;192(50):E1802-E1808. doi:10.1503/cmaj.201085
Sunscreen! Sunscreen! Sunscreen! Have you ever watched a dermatologist go through their skin care routine and not mention sunscreen? No? Me neither! One product that dermatologists unanimously agree on its importance is… you have guessed it! Sunscreen! Sunscreen provides many benefits for the skin starting with decreasing your risk of developing skin cancer. It also has anti-aging benefits as well as aiding in an even skin tone. Sunscreen helps against the damage that the sun can cause onto the skin. Skin cancer is when the outermost layer of the skin, the epidermis, is damaged due to DNA mutation. This leads to an abnormal cell growth in the epidermis. There are four different types of skin cancer that can occur; they are basal cell carcinoma (BCC), squamous cell carcinoma (SCC), melanoma, and Merkle cell carcinoma. Skin cancer mainly occurs from the harmful ultraviolet (UV) rays of the sun as well as the UV used in tanning beds.
The truth is, the word cancer on its own sounds very scary. It has a very negative connotation to it since most times people hear the words cancer then it is assumed to be associated with bad news. When it comes to skin cancer, if it is caught early then there is a great chance of eliminating the cancer before it spreads. Here is what you need to know about the different kinds of skin cancer. BCC is the most common type of skin cancer that occurs in the epidermis. It often develops in areas exposed to the sun such as the face, neck, shoulders, and back. If BCC is caught and treated early, it can be only cause destruction locally but rarely do these cancers spread to other parts of the body and become fatal. The second most common type of skin cancer is SCC. Just like BCC, SCC also occurs in the epidermis and often develops in areas that are exposed to the sun often such as face, neck, and hands and the skin is shown to have signs of sun damage such as wrinkles and age spots. If SCC is not detected and treated early then it can at times grow rapidly and spread which can be fatal. Melanoma is another type of skin cancer that develops from skin cells that produce melanin. Melanin is what gives us our skin color.
Melanoma often appears as a mole and it can be anywhere in the body not necessarily due to exposure to the sun. It can be also caused by tanning beds. It is one of the more rare and dangerous types of skin cancer but it is also curable if it is caught and treated early. Lastly, Merkel cell carcinoma (MCC) is the rarest type of skin cancer and it is very aggressive. It can appear as a painless tumor on an area of the body that is exposed to the sun but there is a high chance of it recurring and spreading throughout the body. Just like other types of cancer, early detection and treatment in crucial especially with MCC.
After learning about the different kinds of skin cancer, it is important to not only apply sunscreen but to understand how to apply it as well as the type of sunscreen that needs to be applied. Sunscreen comes with different protection factors. You may have heard and seen products that have SPF 15, SPF 30, SPF 50, etc. on it but what is the difference between each? Is there really a difference? SPF 15 helps protect against 93% of the UV rays of the sun and SPF 30 helps protect against 97% while SPF 50 protects against 98% of the sun rays. Any SPF that is higher than SPF 50 can protect more against the UV rays but it is an insignificant increase. It is recommended to use SPF 30 or more especially when spending a day outdoors.
Everyone should wear sunscreen daily and should apply it 30 minutes before going outdoors. Reapplication every 2 hours is crucial. There are different types of sunscreens that are present such as physical and chemical sunscreens. Physical sunscreens include ingredients such as zinc oxide and titanium dioxide and may cause less skin irritation than chemical sunscreens but nonetheless both types are safe to be used to protect against UV rays. Sunscreen is a great way to protect yourself against harmful UV rays but it is not completely effective on its own. Wearing long-sleeves, tight clothes, wide-brimmed hat and sunglasses as well as staying in the shade are additional ways that you can protect yourself against harmful UV rays. Stay safe!
Sunscreen will protect the skin against UVA/UVB rays produced by the sun, UV radiation is carcinogenic meaning it is a cause of skin cancer as well as premature skin aging, sunburns and cataracts. Ultraviolet A (UVA) has a longer wavelength and is able to enter the skin barrier leading to premature skin aging. Ultraviolet B (UVB) has a shorter wavelength and will damage the surface of the skin barrier leading to sunburns. Prolonged, unprotected sun exposure to UVB rays will lead to skin cancer more commonly squamous cell carcinoma (SCC), malignant melanoma and basal cell carcinoma (BCC).
Malignant melanoma is the deadliest form of skin cancer, where epidermal melanocytes are affected. Most melanomas are linked to pre-existing moles that a person may have and if it is caught in its early stages it can be surgically removed. BCC and SCC are non-melanomatous skin cancers that affect the epidermal keratinocytes, BCC and SCC are less deadly since they remain localized in the primary affected area. Treatment includes microsurgery, cryosurgery, resection and MOHS.
UV rays will generate reactive oxidative species (ROS) such as hydroxyl radical, superoxide anion, and hydrogen peroxide producing DNA mutations. ROS will cause free radical injury to nucleotide bases which will lead to mutagenesis, for example oxidative change may mutate a G/C pair to A/T pair. Mutations resulting from oxidative mutagenesis are found in tumors isolated from the skin leading to production of carcinogens. UV radiation directly affects nucleotide base pairing in DNA, pyrimidine bases are most susceptible to DNA mutation due to their UV absorption. UV radiation will lead to photo lesions that block DNA replication, impairs transcription and cause abnormal base pairings. UV induced DNA mutations are a major cause of melanomas and other skin cancers, due to the direct mutagenic role of UV radiation.
Sunscreens are vital to sun damage and skin cancer prevention. The two main categories of sunscreens are physical and chemical sunscreens, and come in a variety of forms including sunscreen sticks, oils, creams, liquids, sprays, and gels. Physical sunscreens are also known as mineral sunscreens and contain minerals for example zinc oxide or titanium dioxide. Physical sunscreens will reflect and scatter UVA/UVB rays before the rays entering the skin. Physical sunscreens are generally non-skin irritating and not known to cause many allergic reactions.
Chemical sunscreens contain UVA-absorbing ingredients such as avobenzone/benzophenone as well as UVB-absorbing ingredients. Sunscreens containing para-aminobenzoic acid (PABA) and benzophenone will cause skin reactions such as skin rashes, burning, blisters, redness and itchiness. However many chemical sunscreens have advantages in broader-spectrum coverage against solar radiation, meaning they’ll provide coverage against both UVA and UVB rays.
SPF found in sunscreens stands for sun protection factor, according to the FDA it is a measurement of how much UV radiation is needed to cause sunburns when using sunscreen. The higher the SPF content the longer the sun protection lasts, however the Skin Cancer Foundation recommends using a water-resistant broad spectrum sunscreen with minimum SPF of 30 when outdoors but if one is mostly indoors then SPF of 15 is fine. SPF is often included in other skincare and makeup products, for example some moisturizers, foundations, face powders, even lip balms will contain SPF.
Everyone requires sunscreen year round throughout all four seasons, and it is recommended to apply sunscreen thirty minutes prior to going outside with a re-application every two hours. Also sunscreen application should not only be limited to the face, the body should get a coverage of sunscreen as well. There are a range of sunscreens specifically formulated for the face or body available over the counter. For the ultimate skin protection, one must implement additional skin protection measures. Limit sun exposure as much as possible and avoid tanning beds because they also emit UV radiation also linked to skin cancer.
D'Orazio J, Jarrett S, Amaro-Ortiz A, Scott T. UV radiation and the skin. Int J Mol Sci. 2013;14(6):12222-12248. Published 2013 Jun 7.
Latha MS, Martis J, Shobha V, et al. Sunscreening agents: a review. J Clin Aesthet Dermatol. 2013;6(1):16-26.
Bottom line - everyone should use a broad-spectrum sunscreen with an SPF of 15 or more. (specifically SPF 15 for daily use versus SPF 30+ for extended outdoor activities like a beach trip or hiking trip). Sunscreen includes active ingredients that help prevent the sun’s UV radiation from reaching your skin. There are two broad categories that we can distinguish sunscreen into: physical and chemical sunscreens. Physical sunscreen ingredients block and scatter the rays before the penetrate your skin. Examples of these would be minerals like titanium dioxide and zinc oxide. Chemical sunscreen ingredients absorb the UV rays before they can damage your skin. Examples of these would be avobenzone and octisalate. It is important to note that the sunscreens that are labeled as organic or natural are essentially the same as others that are not. As noted by source 3, it is simply terms used as a marketing strategy. All active ingredients in sunscreens are chemically derived.
People often believe that the higher the SPF, the better the sunscreen. However, this is not true. SPF stands for Sun Protection Factor. This number tells us how long the sun’s UVB rays would take to redden your skin if you were to apply the sunscreen exactly as directed, compared to the amount of time without the sunscreen. Therefore, using an SPF 30 sunscreen would take you 30 times longer to burn than if you did not use the sunscreen.
Source 2 summarizes that sunscreens should not be the first or sole agent used for skin cancer prevention, but should be used in conjunction with clothing to prevent overexposure. There are indications that childhood sun exposure may be particularly important in the generation of basal cell carcinoma and melanoma later in life.
Bottom line - everyone should use a broad-spectrum sunscreen with an SPF of 15 or more. (specifically SPF 15 for daily use versus SPF 30+ for extended outdoor activities like a beach trip or hiking trip). Sunscreen includes active ingredients that help prevent the sun’s UV radiation from reaching your skin. There are two broad categories that we can distinguish sunscreen into: physical and chemical sunscreens. Physical sunscreen ingredients block and scatter the rays before the penetrate your skin. Examples of these would be minerals like titanium dioxide and zinc oxide. Chemical sunscreen ingredients absorb the UV rays before they can damage your skin. Examples of these would be avobenzone and octisalate. It is important to note that the sunscreens that are labeled as organic or natural are essentially the same as others that are not. As noted by source 3, it is simply terms used as a marketing strategy. All active ingredients in sunscreens are chemically derived.
People often believe that the higher the SPF, the better the sunscreen. However, this is not true. SPF stands for Sun Protection Factor. This number tells us how long the sun’s UVB rays would take to redden your skin if you were to apply the sunscreen exactly as directed, compared to the amount of time without the sunscreen. Therefore, using an SPF 30 sunscreen would take you 30 times longer to burn than if you did not use the sunscreen.
Source 2 summarizes that sunscreens should not be the first or sole agent used for skin cancer prevention, but should be used in conjunction with clothing to prevent overexposure. There are indications that childhood sun exposure may be particularly important in the generation of basal cell carcinoma and melanoma later in life.
Sunlight is essential for regulating our sleep patterns and producing vitamin D, which is vital for normal bone function and overall health. However, excessive exposure to sunlight can be harmful. Chronic exposure to ultraviolet (UV) radiation in sunlight is a known cause of nonmelanoma skin cancer. UV rays are classified into two types: UVA and UVB. UVB rays are shorter and can cause sunburn, while UVA rays are longer and can penetrate more deeply into the skin.
UVA rays contribute to skin aging and skin cancer, as they can pass through window glass and are emitted by lamps and tanning booths. A tan induced by UVA rays, such as from a tanning bed, provides 5-10 times less protection against subsequent UV exposure compared to a tan induced by UVB rays. This is because UVA-induced tans result in less noticeable thickening of the epidermis and hyperkeratosis, making the skin more susceptible to damage. UVA rays also suppress the immune system, affecting primary and memory T cell function, and are constant throughout the day and year. UVB rays, while also leading to skin aging and cancer, are more intense during summer, midday, at higher altitudes, and closer to the equator.
Skin cancer is the most common form of cancer in the U.S., with basal cell carcinoma (BCC) being the most prevalent type. BCC typically appears in sun-exposed areas like the face, scalp, ears, chest, back, and legs. These tumors often present as small, dome-shaped bumps with a pearly white color or as recurring sores that bleed, heal, and reappear. An estimated 3.6 million cases of BCC are diagnosed annually in the U.S. More people are diagnosed with skin cancer each year in the U.S. than all other cancers combined, with 1 in 5 Americans developing skin cancer by age 70. The U.S. experiences over two skin cancer-related deaths every hour, and having five or more sunburns doubles the risk of developing melanoma. If melanoma is detected early, the five-year survival rate is as high as 99%.
The International Agency for Research on Cancer, part of the World Health Organization, classifies UV tanning devices as Group 1 carcinogens, a category that also includes plutonium, cigarettes, and solar UV radiation. Risk factors for skin cancer, aside from chronic UV exposure, include light complexion, light eyes, blonde or red hair, freckles, poor tanning ability, easy sunburning, numerous moles, genetics, and history of blistering sunburns.
Preventing skin cancer involves protecting oneself from UV rays by avoiding tanning beds and using sunscreen or protective clothing. Sunscreen contains Sun Protection Factor (SPF), with broad-spectrum SPF covering both UVA and UVB rays. There are two main types of sunscreens: chemical and mineral (or physical). Both are effective and available over the counter. Mineral sunscreens, containing zinc oxide or titanium dioxide, reflect and scatter harmful rays and are usually thick and white, requiring time to rub into the skin. They should be applied at least 15 minutes before sun exposure and are preferred for lighter skin and drier skin types.
Chemical sunscreens also protect against UVA and UVB rays, but some formulations may not fully cover UVA rays. Active ingredients include avobenzone, octinoxate, and oxybenzone. These sunscreens absorb into the skin, where they convert UV rays into heat and release them from the body. Chemical sunscreens do not need to be applied 15 minutes before sun exposure, as they work upon direct contact with the skin. They tend to apply more evenly, do not leave a white cast, and are often more sweat-resistant than mineral sunscreens.
Hung M, Beazer IR, Su S, Bounsanga J, Hon ES, Lipsky MS. An Exploration of the Use and Impact of Preventive Measures on Skin Cancer. Healthcare (Basel). 2022 Apr 15;10(4):743. doi: 10.3390/healthcare10040743. PMID: 35455920; PMCID: PMC9025621.
Sander, Megan et al. “The efficacy and safety of sunscreen use for the prevention of skin cancer.” CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne vol. 192,50 (2020): E1802-E1808. doi:10.1503/cmaj.201085
Sunscreen has become an integral part of one’s daily skincare routine. With companies releasing new products and formulations, people have many options to choose from. Each sunscreen has different characteristics and may set differently on various types of skin. Sunscreen works to protect against UV radiation. It has usually been primarily used for sunburn prevention. However, with the progressing science industry, we can see the importance of protecting ourselves against skin cancer, skin damage, and skin aging. In the past few decades, many studies have been conducted to formally assess the efficacy of sunscreens. Online influencers even perform at-home self-studies to compare the latest sunscreens on the market. Several randomized controlled trials displayed a reduction in the risk of squamous cell and melanoma cancers. Skin cancer is one of the most common cancers in the United States, requiring adequate protection against UVR.
Sunscreens are available as sprays, gels, lotions, and solid blocks. However, there are two main types of sunscreen: chemical and mineral. Mineral sunscreens contain minerals such as zinc oxide and titanium oxide which sit on top of the skin upon application. Chemical sunscreens, on the other hand, get absorbed into the skin. Mineral sunscreens reflect UV rays, whereas chemical sunscreens, which contain UV filters such as oxybenzone and octinoxate, deactivate the rays upon absorption into the skin. Mineral sunscreens have immediate effectiveness while chemical sunscreens take approximately 20 minutes to fully work. As mineral sunscreens contain an astringent such as zinc oxide, it’s more likely to cause dryness. The minerals cause the sunscreen to have a thicker consistency which may lead to a white cast formed on the skin. This makes it difficult for individuals with darker skin to find an appropriate sunscreen. Many people may opt for chemical sunscreens due to their hydrating abilities, lack of a whitecast, and blendability. However, due to their active ingredients, individuals are more likely to experience allergic reactions, irritation, and clogged pores. The FDA has even inquired into the UV filters used in chemical sunscreens, stating the absorption into the skin, into the bloodstream, may negatively impact one's health. Although no official statement has been released, many have stated that the benefits of protection against skin cancer outweigh the risks.
Sunscreens state their SPF, otherwise known as, sun protection factor. This measures how much the product will protect you from UVB and UVA rays. It is important to use a minimum of SPF 30. It may be a game of trial and error in the beginning before you select the product that works for you. One thing that many individuals, myself included, forget to do is reapply sunscreen. Sunscreen usually needs to be reapplied every 2 hours. Sunscreen also needs to be reapplied after swimming or sweating. It is also a misconception to wear sunscreen on sunny days. UV rays are still present on a cloudy day. Many medications such as benzoyl peroxide, doxycycline, and voriconazole require sun protection, or else photosensitivity reactions such as redness, itchiness, pain, and rash may occur. Individuals should educate themselves about the benefits of sun protection and research which products work best for their skin.
References
https://pubmed.ncbi.nlm.nih.gov/25207381/
https://pubmed.ncbi.nlm.nih.gov/33721254/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7759112/
Skin cancer is a widespread form of cancer, with millions of new cases diagnosed annually. Its primary cause is exposure to ultraviolet (UV) radiation from the sun, which can harm the DNA in skin cells, leading to mutations that may result in cancerous growths. However, the risk of developing skin cancer can be significantly lowered by using sunscreen.
Sunscreen as we know is a topical product applied to the skin to shield it from the harmful effects of UV radiation. It functions by absorbing or reflecting UV radiation, thus preventing it from penetrating the skin and causing damage. Available in various formulations such as lotions, creams, gels, sprays, and sticks, sunscreens differ in their sun protection factor (SPF) and the types of UV radiation they guard against.
SPF indicates a sunscreen's ability to protect the skin from UVB radiation, the primary cause of sunburn and a significant factor in skin cancer development. The higher the SPF value, the greater the protection provided. For instance, SPF 30 sunscreen shields against about 97% of UVB radiation, while SPF 50 sunscreen protects against about 98%. Using sunscreen with an SPF of at least 30 is recommended for adequate protection.
Apart from SPF, it's crucial to consider the broad-spectrum protection offered by sunscreen. Broad-spectrum sunscreens shield against both UVA and UVB radiation. UVA radiation penetrates the skin more deeply than UVB radiation and can lead to premature skin aging and an elevated risk of skin cancer. Hence, using a broad-spectrum sunscreen helps protect against both types of UV radiation.
When applying sunscreen, it's important to cover all exposed areas generously at least 15-30 minutes before going outside. This allows the sunscreen to absorb fully and provide maximum protection. Reapply sunscreen every two hours or immediately after swimming, sweating, or towel drying, as these activities can reduce its effectiveness.
Despite sunscreen's benefits, studies show that many people do not use it consistently or correctly, leading to inadequate protection and an increased risk of skin cancer. Educating the public about sun protection's importance and the correct application of sunscreen is essential to encourage its proper use.
In conclusion, sunscreen plays a crucial role in shielding the skin from UV radiation's harmful effects and reducing the risk of developing skin cancer. By using broad-spectrum sunscreen with an adequate SPF and applying it correctly and consistently, individuals can safely enjoy the sun while minimizing their risk of skin cancer.
References:
Hung M, Beazer IR, Su S, Bounsanga J, Hon ES, Lipsky MS. An Exploration of the Use and Impact of Preventive Measures on Skin Cancer. Healthcare (Basel). 2022 Apr 15;10(4):743. doi: 10.3390/healthcare10040743. PMID: 35455920; PMCID: PMC9025621.
Skin cancer: Types and treatment. American Academy of Dermatology. https://www.aad.org/public/diseases/skin-cancer/types.
The Importance of Sunscreen in Preventing Skin Cancer
Sunscreen is a fundamental component of a healthy skincare routine, playing a pivotal role in safeguarding the skin against the damaging effects of ultraviolet (UV) radiation from the sun. Beyond its benefits, such as preventing sunburn and premature aging, the importance of sunscreen extends to the prevention of more severe consequences like skin cancer. As a crucial line of defense, sunscreen helps shield the skin from harmful UVA and UVB rays, emphasizing the significance of incorporating this protective measure into daily skincare practices. This introduction explores the importance of sunscreen in preventing skin cancer.
To understand how sunscreen can prevent skin cancer, we must understand how UV rays work. There are three types of UV rays: UVA, UVB, and UVC. UVC radiation is removed by the ozone layer, thus UVA and UVB cause the most damage. UVA rays reach all the way into the dermis, while UVB rays reach the top layer of the dermis. UVA rays are passed through car passenger windows, produced by lamps and tanning booths, and are constant throughout the day and year. UVA rays penetrate more deeply than UVB rays and they are used in tanning booths to produce a tan. These tans increase your risk of skin cancer and provide less protection from sun exposure than a UVB ray tan. UVB rays are responsible for most skin damage like sunburns, as these rays are more intense in the summer, midday, at high altitudes, and closer to the equator. In addition to UV risk, those with a light complexion, light eyes, blonde or red hair, many freckles, tan poorly/sunburn easily, and many moles are at a higher risk of skin cancer through sun exposure.
There are physical ways of blocking the sun that should be recommended to all patients. For example, wearing protective clothing such as long pants, a long sleeved shirt, and a hat with a wide brim. Clothing items that are tightly woven and dark in color can block out more UVR. For high risk patients, those spending more time in the sun during peak times, sunscreen should be utilized. Complete avoidance of UVR is key to preventing UVR induced skin disorders. Although we understand, that is not feasible for everyone. We should equip our patients with the necessary tools and information to pick out the best sunscreen for them.
SPF is a common term everyone is familiar with. It stands for sun protection factor. The SPF value is calculated based on the ratio of the time it takes for UVB radiation to cause noticeable redness on the skin with the sunscreen versus without it. For example, if a person typically starts to experience sunburn after 10 minutes of sun exposure without sunscreen, applying sunscreen with SPF 30 theoretically extends that time to 300 minutes (10 minutes x 30 SPF).SPF15+ is recommended for all patients. At this protection factor, UVA and UVB protection are also guaranteed. The FDA regulates sunscreens to make sure their effectiveness is met. The FDA has proposed that it is not necessary to use an SPF over 60, as there are no significant differences in benefits shown with a higher SPF.
Additionally, there are two different types of topical sunscreens: chemical and physical. Chemical sunscreens use organic compounds like avobenzone or oxybenzone to absorb UV radiation and convert it into heat, which is then released from the skin. Physical sunscreens contain minerals like zinc oxide or titanium dioxide that form a physical barrier on the skin that reflects UV rays. Some prefer chemical sunscreens as it leaves less of a white cast but physical sunscreens can block both UVB and UVA rays.
In short, to understand how skin cancer can be prevented, one must understand the importance of sunscreen and its ability to block UV rays.
For my in depth into skin cancer, please reference my past post: https://www.the-socioesthetician-international.com/forum/main/comment/32e8e98e-32a4-425d-941e-3a0cc17c339e?postId=6075ebad55765f002c0868a6
References:
Kimberly M. Crosby, (2020), "Chapter 39: Prevention of Sun-Induced Skin Disorders," Handbook of Nonprescription Drugs: An Interactive Approach to Self-Care, 20th Edition https://doi-org.jerome.stjohns.edu/10.21019/9781582123172.ch39
Sunlight is essential for the human body to keep our sleeping patterns on track and producing vitamin D, which is important for normal bone function and health. However, just like anything else, being exposed to too much of something is never healthy. The same applies with sunlight as well, and it is already known that chronic exposure to ultraviolet or UV radiation present in sunlight is responsible for nonmelanoma skin cancer. There are two types of UV rays, classified as UVA rays and UVB rays. UVB rays are shorter rays that can lead to sunburn if exposed too much to it, however UVA rays are the longest rays and have the ability to travel more deepy into the skin.
Some effects of UVA rays on the skin includes skin aging and skin cancer, as they pass through window glass and are also produced by lamps and tools such as tanning booths. A tan induced by UVA, such as through tanning bed use, offers 5-10 times lower protection against sunburn from subsequent UV exposure compared to a tan induced by UVB. This is likely attributed to the less noticeable thickening of the epidermis and hyperkeratosis associated with a UVA-induced tan. This way, there is more exposure to it from people and as a result they are more prone to develop disease. UVA rays suppress the immune system which affects the primary and memory T cell function and are also constant throughout the day and year. UVB rays can also lead to skin aging and cancer and are responsible for most skin damage. They are more intense in the summer, midday, higher altitudes, and are closer to the equator.
Skin cancer is the most common form of cancer in the U.S. and basal cell carcinoma (BCC) is the most common form of skin cancer. Basal cell carcinoma typically manifests in areas exposed to sunlight, including the face, scalp, ears, chest, back, and legs. These tumors can exhibit various forms, with the prevalent presentation being a small, dome-shaped bump displaying a pearly white color. Another frequently observed indication is a recurring sore that bleeds, heals, and reappears. An estimated 3.6 million cases of BCC are diagnosed in the U.S. each year. More people are diagnosed with skin cancer each year in the U.S. than all other cancers combined. 1 in 5 Americans will develop skin cancer by the age of 70. The U.S. witnesses over two skin cancer-related deaths every hour. Having five or more sunburns doubles the likelihood of developing melanoma. If melanoma is identified early, the 5-year survival rate is as high as 99%.
The International Agency for Research on Cancer, an affiliate of the World Health Organization, includes ultraviolet (UV) tanning devices in its Group 1, a list of agents that are cancer-causing to humans. Group 1 also includes agents such as plutonium, cigarettes and solar UV radiation. Some risk factors aside from chronic UV expsure includes light complexion, light eyes, blonde or red hair, many freckles, tanning poorly and sunburning easily, many moles, genetics, blistering sunburns.
Prevention of skin cancer includes protecting oneself from UV rays by avoiding tanning beds and blocking them using sunscreen or protecting clothing. Sunscreen contains SPF which stands for Sun Protective Factor and broad spectrum SPF covers both UVA and UVB rays.
References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC113773/
https://newsinhealth.nih.gov/2014/07/sun-skin#:~:text=Sunlight%20also%20helps%20our%20skin,waves%2C%20are%20harmless%20to%20people.
https://www.skincancer.org/skin-cancer-information/skin-cancer-facts/#:~:text=About%2090%20percent%20of%20nonmelanoma,UV)%20radiation%20from%20the%20sun.&text=Basal%20cell%20carcinoma%20(BCC)%20is,in%20the%20U.S.%20each%20year.
Some sun is never a bad thing. The exposure of sun to the skin helps to produce vitamin D, which helps calcium absorption for stronger and healthier bones. However, when you get constant exposure to the sun without any protection ultraviolet (UV) sun rays can cause major damage to the skin. This damage can vary from early aging, wrinkles, scarring all the way to cancer.
Ultraviolet (UV) radiation is energy from the some that makes it to the earth. It is a form of electromagnetic radiation. Although there are three types of UV radiation, the earth only received UVB and UVA. UVA rays have the least energy so damage to the skin usually includes wrinkles and aging. However, it can indirectly damage cells DNA. UVB rays are much more powerful than UVA, this type of radiation exposure causes direct cell DNA damage to the skin. UVB causes sunburns and skin cancer. The sun mostly emits UVB and that is the main source of this type of radiation. Ultraviolet radiation is most prominent during the middle of the day when the Sun is at its highest. UV radiation is also more common during the hot months of the year like Spring and Summer.
Protection against UV radiation important to avoid any of the unwanted side effects that are very harmful to a person. We protect against these UV rays using sunscreen, proper clothing, and avoidance of the sun in excess. There are two types of sunscreens, chemical sunscreens, or mineral sunscreens. Both are sold in drug stores over the counter and are effective in the protection against UV rays. Mineral sunscreen is also known as physical sunscreen. The main ingredients for these sunscreens include zinc oxide or titanium dioxide. These drugs reflect and scatter harmful rays from the sun. Mineral sunscreen is seen usually as thick and white, they take a minute to rub into the skin to get it evenly coated. These types of sunscreens should be placed on the skin at least 15 minutes before sun exposure to ensure maximum efficacy. Overall, mineral sunscreen is preferred for people with lighter skin due to the white cast and drier skin types.
Chemical sunscreens protect against both UVA and UVB rays, however some variations and ingredients are questionable in covering UVA rays. The active ingredients in these kinds of sunscreens include avobenzone, octinoxate and oxybenzone. Chemical sunscreens absorb into the skin and then absorbs UV rays converts the rays into heat and releases them from the body. This type of sunscreen doesn’t need to be applied 15 minutes before sun exposure it works on direct contact to skin. These types of sunscreens apply more evenly and often do not leave a white cast on the skin. Chemical sunscreens tend to be more sweat resistant that mineral sunscreens.
Overall, both sunscreen types are effective in the protection of UV rays and preventing unwanted harm to the skin. Both should always be reapplied throughout the day to get the maximum effect of the product. Something so simple as applying sunscreen daily can having life changing effects for people in the long run. Skin cancer is so common and often it is caught when at the deeper stages, making it harder to treat.
References:
Sander, Megan et al. “The efficacy and safety of sunscreen use for the prevention of skin cancer.” CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne vol. 192,50 (2020): E1802-E1808. doi:10.1503/cmaj.201085
“UV Radiation.” Centers for Disease Control and Prevention, 5 July 2022, www.cdc.gov/nceh/features/uv-radiation-safety/index.html#:~:text=UV%20radiation%20is%20classified%20into,some%20UVB%20radiation%20reaches%20earth.
Solid organ transplantation has revolutionized the treatment of end-stage organ failure, promoting the survival and quality of life of patients. However, solid organ transplant recipients (OTRs) face an increased risk of developing skin cancer, compared to the general population. The increased susceptibility is primarily attributed to the long-term immunosuppressive therapy required to prevent organ rejection which impairs the immune system’s ability to monitor for atypical cells. OTRs have a 65-250-fold and 6-16-fold greater risk of developing cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) than the general population, respectively; other cancers such as melanoma, Merkel cell carcinoma and Kaposi sarcoma are also more common in OTRs, but less likely than SCC (and BCC).
The pathways related to cutaneous malignancy in OTRs are not fully understood but it is generally accepted that immunosuppressive agents play a major role. As previously mentioned, immunosuppression results in reduced immune surveillance, leading to increased survival and proliferation of atypical cells. Immunosuppressive medications – especially azathioprine and cyclosporine – have been linked to the development of skin cancer in multiple trials. Azathioprine has been associated with mutagenic effects following UV radiation-exposure, while cyclosporine has been associated with changes in cell morphology and inhibition of DNA repair. Furthermore, immunosuppression allows for proliferation of oncogenic viruses such as Epstein-Barr virus, human papillomavirus, Kaposi sarcoma herpes virus, and Merkel cell polyomavirus which are associated with the development of cancer in these patients. Several risk factors also contribute to the elevated incidence of skin cancer in OTRs. A large cohort of >10,000 solid OTRs showed that 8% of patients evaluated developed a post-transplant skin cancer. The main predictors of skin cancer included: pre-transplant skin cancer (hazard ratio [HR] 4.69, 95% CI 3.61-6.09), male sex (HR 1.61, 95% CI 1.34-1.89), thoracic organ transplant (heart or lung) (HR 1.51, 95% CI 1.26-1.82), white race (HR 7.79, 95% CI 5.34-11.37), and ≥50 years at time of transplantation (HR 2.65, 95% CI 2.12-3.21). Other notable risk factors include past overexposure to UV radiation and history of transplant rejection. OTRs are also at an increased risk of additional lesions following SCC or BCC development; one study found the cumulative incidence of a second SCC was 44%, 67% and 76% after 1, 3 and 5 years, respectively.
The clinical manifestations of skin cancer in OTRs typically resemble those seen in the general population but may develop in unusual sites or exhibit atypical features (more often with SCC than BCC). Additionally, OTRs often present with multiple, more aggressive tumors, necessitating a high index of suspicion. Preventive measures play a pivotal role in mitigating the risk of skin cancer development and increased mortality in OTRs, requiring close collaboration with dermatologists and the transplant team. Prior to and following transplantation, OTRs should be educated on the importance of sun protection. The use of daily broad-spectrum sunscreen, sun-protective clothing, and avoidance of excessive sun exposure (especially during peak hours) should be emphasized. OTRs should be instructed to perform monthly skin self-examinations and report any suspicious lesions immediately; the American Academy of Dermatology provides online tutorials for patients to refer to. Since the intensity and duration of immunosuppressive regimens promotes the development of cutaneous malignancies in OTRs, reduction of immunosuppression may be considered in patients with multiple lesions, recurrent or metastatic disease. However, there is insufficient evidence evaluating the effects of immunosuppression reduction and reduction may increase the risk of organ rejection; thus, the risks and benefits must be carefully considered. If medically feasible, some studies have shown that mTOR inhibitors (such as sirolimus and everolimus) or mycophenolate mofetil are associated with a lower incidence of skin cancer than azathioprine and may be a safer option for OTRs than immunosuppression reduction.
References
Berman H, Shimshak S, Reimer D, et al. Skin cancer in solid organ transplant recipients: a review for the nondermatologist. Mayo Clin Proc. 2022 Dec;97(12):2355-68. https://www.mayoclinicproceedings.org/article/S0025-6196(22)00433-5/fulltext
Garrett GL, Blanc PD, Boscardin J, et al. Incidence of and risk factors for skin cancer in organ transplant recipients in the United States. JAMA Dermatol. 2017 Mar;153(3):296-303. https://jamanetwork.com/journals/jamadermatology/fullarticle/2596399
Stasko T, Hanlon AM. Epidemiology, and risk factors for skin cancer in solid organ transplant recipients. Wolters Kluwer: UpToDate. 2023 Mar. https://www-uptodate-com.jerome.stjohns.edu/contents/epidemiology-and-risk-factors-for-skin-cancer-in-solid-organ-transplant-recipients#H7860379
Stasko T, Hanlon AM. Prevention, and management of skin cancer in solid organ transplant recipients. Wolters Kluwer. 2023 Jul. https://www-uptodate-com.jerome.stjohns.edu/contents/prevention-and-management-of-skin-cancer-in-solid-organ-transplant-recipients#H2295753
Importance of sunscreen
Yu Feng Lin & Fawziya Twam
The importance of sunscreen is well-established in evidence-based medicine. Sunscreen helps protect the skin from the harmful effects of ultraviolet (UV) radiation from the sun, and its benefits are supported by extensive scientific research. Skin cancer, including melanoma, basal cell carcinoma, and squamous cell carcinoma, is strongly linked to UV radiation exposure from the sun. Multiple studies have shown that regular sunscreen use can significantly reduce the risk of skin cancer. For example, a study published in the Journal of Clinical Oncology in 2011 found that daily sunscreen use reduced the risk of melanoma by 50-73% compared to infrequent use.
A common visual of sun damage is sunburn. Many people experience sunburn due to being in UV rays for long periods of time and not having their skin properly protected. Sunburn is not only painful but also a clear indication of skin damage from UV radiation. Clinical studies have demonstrated that applying sunscreen with a high sun protection factor (SPF) can effectively prevent sunburn and reduce the immediate damage caused by UV exposure. Chronic sun exposure can lead to premature aging of the skin, including wrinkles, fine lines, and age spots. Evidence-based research has shown that sunscreen use helps prevent and delay the signs of premature skin aging, keeping the skin looking younger and healthier.
UV radiation can cause DNA damage and oxidative stress in the skin, leading to various skin conditions and disorders. One major consequence of DNA damage to the skin cells from UV radiation is unfortunately skin cancer. Studies have indicated that sunscreen can help mitigate this damage by reducing the harmful effects of UV radiation on the skin's cells and structures.
Some individuals suffer from photosensitive skin conditions (photodermatoses) that can be aggravated by UV exposure. Photosensitivity is also a possible side effect from certain medications. When taking certain drugs such as NSAIDs, sulfonylureas, antihistamines and others, it should be noted that photosensitivity is a possibility and to use protection. Sunscreen is an essential part of managing these conditions, as it provides a physical barrier against UV radiation. After certain skin procedures, such as chemical peels, laser treatments, or surgery, the skin is highly sensitive and vulnerable to UV damage. Dermatologists often recommend the use of sunscreen to protect the healing skin and minimize the risk of complications.
Evidence from a variety of sources underscores the critical role of sunscreen in protecting the skin from the detrimental effects of ultraviolet radiation from the sun. Notably, both observational studies and large-scale randomized controlled trials (RCTs) have consistently supported the effectiveness of sunscreen in preventing signs of photoaging, such as wrinkles, telangiectasia, and pigmentary alterations induced by UV radiation. These findings emphasize the cosmetic and aesthetic benefits of sunscreen use in maintaining youthful and healthy skin.
Evidence from multiple studies and randomized controlled trials strongly suggests that sunscreen plays a pivotal role in preventing skin cancer, particularly squamous cell carcinomas. Experimental studies conducted in the 1980s and 1990s demonstrated that sunscreens can shield against cell damage consistent with carcinogenesis in animal models. Importantly, a well-conducted, community-based RCT involving adult Australians revealed a substantial 40% reduction in the incidence of squamous cell carcinomas among participants who used sunscreen daily as recommended, compared to those who used it less frequently. Although the incidence of basal cell carcinomas did not significantly decrease, this can be attributed to the protracted development of these tumors.
The long-term benefits of sunscreen use are evident in reduced risks of invasive melanoma, even many years after the study's completion. Additionally, sunscreen has been shown to halt signs of skin aging caused by photodamage, emphasizing its role in preserving skin health and appearance over time. In organ transplant recipients, a high-risk population for skin cancer, the regular use of sunscreen, particularly with a high SPF rating, led to a notable reduction in the development of actinic keratoses and various types of skin carcinomas.
While recent meta-analyses have raised some questions regarding the efficacy of sunscreen in preventing skin cancer, it is important to consider that these analyses included studies with varying methodologies and sunscreen formulations. Nevertheless, the highest-quality evidence available, including well-designed RCTs and experimental studies, collectively demonstrates that sunscreen is a valuable tool in reducing the risk of skin cancer and maintaining skin health. As such, sunscreen remains a recommended and evidence-based measure for safeguarding skin from the harmful effects of UV radiation.
Sunscreen is an integral component of maintaining overall skin health and preventing a wide range of skin problems associated with UV radiation exposure. The importance of sunscreen in evidence-based medicine is well-documented. Regular and proper use of sunscreen is a proven strategy to reduce the risk of skin cancer, prevent sunburn, delay premature aging, and protect the skin from UV-induced damage. Dermatologists and health organizations worldwide recommend sunscreen as a crucial part of a comprehensive sun protection strategy to promote skin health.
References:
Henderson, S. I., King, K. L., Karipidis, K. K., Tinker, R. A., & Green, A. C. (2022). Effectiveness, compliance and application of sunscreen for solar ultraviolet radiation protection in Australia. Public health research & practice, 32(1), 3212205. https://doi.org/10.17061/phrp3212205
Sander, M., Sander, M., Burbidge, T., & Beecker, J. (2020). The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne, 192(50), E1802–E1808. https://doi.org/10.1503/cmaj.201085
Sunscreen & Skin Cancer
Skin cancer is one of the most prevalent cancers in the United States. The main risk factor is ultraviolet (UV) radiation exposure from the sun. Sunscreen is made to protect the skin against these harmful UV rays, thus reducing one’s risk of skin cancer. There are three different types of UV rays including UVA, UVB, and UVC. The two rays that can penetrate the earth's atmosphere are UVA and UVB. Therefore, they can reach the skin and cause mutations in the individual's DNA leading to skin cancer. Sunscreen’s purpose is to block both of these UV rays by either absorbing or reflecting them. Chemical sunscreens have organic compounds that absorb the rays, while physical sunscreens contain zinc oxide or titanium dioxide that reflects the UV rays.
UVB rays cause sunburn and are also the main cause of non-melanoma cancers such as basal cell carcinoma and squamous cell carcinoma. Sunscreen is classified by chemical or physical as well as, the sun protection factor (SPF). The SPF indicates what level of protection one will receive from UVB rays. For example, SPF 30 can protect against about 97% of UVB rays. There is no sunscreen that will give 100% protection however, it is still important to wear it. UVA rays, on the other hand, are involved in skin aging and some skin cancer. They are able to penetrate the skin deeper thus, causing damage to elastin and collagen which can lead to premature wrinkles. There are sunscreens available that can protect against both kinds of UV rays called broadspectrum. For sunscreen to protect the skin effectively, it must be applied correctly and in timely intervals. It is recommended to apply sunscreen about 15-30 minutes before being exposed to the sun and every 2 hours while outside.
Multiple studies have demonstrated the effectiveness of sunscreen in reducing the risk of skin cancer. A systematic review and meta-analysis published in the Journal of Clinical Oncology in 2018 analyzed data from 19 studies and found that regular sunscreen use was associated with a significant reduction in the risk of melanoma, the most deadly form of skin cancer. Another study published in the Journal of the American Academy of Dermatology in 2019 showed that daily sunscreen use led to a 50% reduction in the incidence of melanoma, squamous cell carcinoma, and basal cell carcinoma combined.
References:
Hung M, Beazer IR, Su S, Bounsanga J, Hon ES, Lipsky MS. An Exploration of the Use and Impact of Preventive Measures on Skin Cancer. Healthcare (Basel). 2022 Apr 15;10(4):743. doi: 10.3390/healthcare10040743. PMID: 35455920; PMCID: PMC9025621.
Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020 Dec 14;192(50):E1802-E1808. doi: 10.1503/cmaj.201085. PMID: 33318091; PMCID: PMC7759112.
Sunscreen is an important part of our day-to-day lives as it is one of the best and easiest ways to protect the skin from the sun’s rays. These rays, ultraviolet have subtypes A and B, both of which cause radiation to reach us. While we do get vitamin D from the sun, there is also the risk of serious health issues, such as cancer. According to the CDC, “Skin cancer is the most common cancer in the United States. The two most common types of skin cancer are basal cell cancer and squamous cell cancer. Typically, they form on the head, face, neck, hands, and arms because these body parts are the most exposed to UV radiation. Most cases of melanoma, the deadliest kind of skin cancer, are caused by exposure to UV radiation.” People at risk for these are typically those with lighter hair/skin color, who spend a lot of time in the sun, and even those who take products that may cause photosensitivity, such as antibiotics and birth control pills.
There are 2 different types of sunscreens on the market. The more common one, mineral sunscreen, is usually made from either zinc oxide or titanium oxide, or both. Chemical sunscreens, on the other hand, contain oxybenzone, avobenzone, and/or octocrylene. Although they do the same job, they act differently which may impact what we should recommend to a patient seeking advice. Mineral sunscreen act on UV reflection while chemical sunscreens work on UV absorption. These characteristics affect the stability of the product. Mineral sunscreen is more efficient and stable, while chemical sunscreen can break down more easily. It’s also worth noting that chemical sunscreens can have interactions with other chemicals. An important one to note is oxybenzone and chlorine, commonly found in pools. When comparing their ability to effectively protect against radiation, it is seen that mineral sunscreens are typically available at lower SPF when compared to chemical sunscreens. Additionally, it is noticed by consumers that mineral sunscreen is more prone to leaving a chalky appearance on the skin, which may not be admirable. Chemical sunscreens are more likely to blend into the skin and make it look like there is no product there.
With the summer months coming, we get a lot of patients coming in and asking us which sunscreen is recommended and which is better for protection against the sun. As of right now, I feel that the differences are slightly above negligible. Both options help protect against UVB radiation. Something to consider is what occasion the patient is using the sunscreen for. If they are going to the beach or the pool, then maybe they should stick with a mineral sunscreen, in case the chemicals in the chemical sunscreen react with something in the water. If they want to use it for day-to-day protection, then maybe a chemical sunscreen would be better since it has a more natural finish than minerals. Recently, there have been products that have come out with a combination of mineral and chemical sunscreen in one product, but it is unclear which is better when compared to its isolated counterparts
Resources
Varedi, A., Wu, Y. P., Klein, S. Z., Leachman, S. A., & Grossman, D. (2019). Mineral sunscreens not recommended by Consumer Reports: Suggestions to improve the review process. Journal of the American Academy of Dermatology, 80(3), 832–833. https://doi.org/10.1016/j.jaad.2018.09.009
“UV Radiation.” Centers for Disease Control and Prevention, 5 July 2022, www.cdc.gov/nceh/features/uv-radiation-safety/index.html#:~:text=UV%20radiation%20is%20classified%20into,some%20UVB%20radiation%20reaches%20earth.
UV Radiation & Skin Cancer
Ultra violet (UV) radiation is a form of electromagnetic radiation that naturally is emitted from the sun. There are three different types of UV radiation: UVA, UVB, and UVC. UVA rays have the least energy but can cause skin cells to age and can cause indirect damage to cells’ DNA. UVA is linked to long-term skin damage like wrinkles. UVB rays have more energy than UVA rays and can directly damage cells’ DNA. These rays are the main cause of sunburn and cause the most skin cancers. UVC rays have the highest energy of the three but they do not pose a risk to humans due to the fact that they react with ozone in the atmosphere before they are able to reach the ground. Sunlight is the main way that humans are exposed to UV radiation although there are some manmade mechanisms such as tanning beds and welding torches. UVA and UVB rays are not equally emitted by the sun. about 95% of the UV rays are UVB while 5% are UVA. The strength of the rays reaching humans varies according to several different factors. UV rays are strongest midday (10am-4pm) as well as during the spring and summer seasons. Exposure to UV radiation decreases as your location gets farther from the equator. UV radiation exposure may also be increased in areas with water, sand, snow, or pavement due to the rays’ ability to bounce off these surfaces (American Cancer Society).
There are three main types of skin cancer that can be caused by UV radiation: basal cell carcinoma, squamous cell carcinoma, and melanoma. These three types vary in their origin, severity, and treatment. Basal cell carcinoma (BCC) is the most common type of skin cancer. It originates in the basal cells of the skin and looks like a flesh-colored round growth, pearl-like bump, or a pinkish patch of skin. This type is common on the head, neck, and arms. Squamous cell carcinoma (SCC) is the second most common type of skin cancer and looks like a red firm bump scaly patch, or a sore than heals and then reopens. This type tends to form on skin that gets the most sun exposure like the rim of the ear, face, neck, arms, chest, and back. Melanoma is the most serious type of skin cancer with the highest tendency to spread to other tissues. It can develop within a mole already present on the skin or appear as a dark spot. Each of these types of skin cancer occur at a higher rate in people with lighter complexions (American Academy of Dermatology).
Treatment of basal cell carcinoma involves standard surgical excision as first-line treatment. Curettage and electrodesiccation is an alternative first-line option in which the affected skin is scraped off. Similar to BCC, SCC also involves standard surgical excision as a first-line treatment option. Mohs surgery which is a specialized tissue-sparing procedure is also an option for SCC. Melanoma is usually treated by removing the affected cells by wide excision. Wide excision of melanoma is generally performed down to the muscle fascia unlike the excision used for BCC or SCC. Depending on whether or not the melanoma has spread, treatment may include more invasive therapy (Gershenwald). While the surgical removal of skin cancer is a viable treatment option, it is still best to prevent skin cancer from occurring in the first place by staying out of the sun at an early age or wearing protective clothing when being in the sun is unavoidable.
Resources:
Gershenwald J, Keung E. Surgical management of primary cutaneous melanoma. UpToDate. https://www.uptodate.com/contents/surgical-management-of-primary-cutaneous-melanoma-or-melanoma-at-other-unusual-sites?search=treatment+of+melanoma&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2#H1701593750. Accessed March 15, 2022.
Skin cancer: Types and treatment. American Academy of Dermatology. https://www.aad.org/public/diseases/skin-cancer/types. Accessed March 15, 2022.
Ultraviolet (UV) radiation. American Cancer Society. https://www.cancer.org/cancer/cancer-causes/radiation-exposure/uv-radiation.html#:~:text=UV%20rays%2C%20either%20from%20the,actinic%20keratosis%2C%20and%20solar%20elastosis. Published July 10, 2019. Accessed March 15, 2022.
Sunscreen and Skin Cancer
The sun is the skin’s worst enemy. Sun exposure can lead to sunburns which increases the risk of skin cancer. Skin cancer starts when abnormal cells in the epidermis are growing out of control. The main types of skin cancer are basal cell carcinoma, squamous cell carcinoma and melanoma. Basal cell carcinoma is the most common form of skin cancer, and is caused by a combination of intermittent, intense exposure and cumulative, long-term exposure to UV radiation from the sun. It usually develops on skin areas typically exposed to the sun such as the face, ears, neck, scalp, shoulders and back. Squamous cell carcinoma is the second most common form of skin cancer, and is caused by cumulative, long-term exposure to UV radiation from the sun and tanning beds. It usually develops on sun-exposed areas. Melanoma is the most dangerous form of skin cancer, and it is estimated that there will be 197,700 new cases in the U.S. in 2022. It is caused by intense, intermittent sun exposure and tanning beds. It can be found anywhere on the body, even in areas that are not typically exposed to the sun.
The use of sunscreen can reduce the danger posed by UV radiation. UV radiation is part of the natural energy produced by the sun, and there are two types of UV light that contribute to the risk of skin cancer. UVA accounts for 95% of UV radiation that reaches the Earth’s surface with fairly constant intensity over the day. It penetrates the ozone, clouds, and window glass. It also penetrates the human skin more deeply and is associated with skin aging. UVB, on the other hand, accounts for 5% of the UV radiation that reaches the Earth’s surface with varied intensity that peaks around midday. It is partially absorbed by the ozone and clouds and does not penetrate window glass. It is not absorbed as deeply into the skin and is associated with skin burning. UVA is connected to the “broad-spectrum protection” and UVB is connected to the Sun Protection Factor (SPF) on sunscreen product labels. SPF indicates how long the sun’s radiation would take to redden your skin with sunscreen compared to without sunscreen.
There are two types of sunscreen: physical (mineral) and chemical. Physical sunscreen has ingredients like titanium dioxide and zinc oxide, and they block and scatter UV rays before it penetrates the skin. Chemical sunscreen has ingredients like oxybenzone, avobenzone, octocrylene and ecamsule, and they absorb UV rays before it damages the skin. Physical sunscreens may cause less skin irritation than chemical sunscreens, but both are tested as safe and effective.
Everyone over the age of 6 months should be using sunscreen daily that is broad spectrum with an SPF 15 or higher. It is found that using SPF 15 sunscreen daily can reduce the risk of developing squamous cell carcinoma by about 40 percent. SPF 15 is ideal for daily use, but SPF 30 or higher is necessary for extended outdoor activities. No matter the SPF, sunscreen should be applied 30 minutes before going outside and reapplied every two hours and immediately after swimming or sweating. It is necessary to apply sunscreen daily, even when it is cloudy because up to 80 percent of UV radiation reaches the earth. Sunscreen application should not be limited only to the face, but also to the entire body.
Sunscreen alone isn’t enough, going under the shade and wearing sun-safe clothing, a wide-brimmed hat and UV blocking sunglasses are also important.
References:
1. Green AC, Williams GM. Point: sunscreen use is a safe and effective approach to skin cancer prevention. Cancer Epidemiol Biomarkers Prev. 2007;16(10):1921-1922. doi:10.1158/1055-9965.EPI-07-0477
2. Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020;192(50):E1802-E1808. doi:10.1503/cmaj.201085
3. “Skin Cancer Information.” The Skin Cancer Foundation, 20 Jan. 2022, https://www.skincancer.org/skin-cancer-information/.
4. “Sunscreen.” The Skin Cancer Foundation, 28 Jan. 2022, https://www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/.
5. “UV Radiation.” The Skin Cancer Foundation, 28 Jan. 2022, https://www.skincancer.org/risk-factors/uv-radiation/.
Melanoma
Melanoma is the most serious form of skin cancer due to its ability to quickly spread to other organs if not detected at an early stage. This type of skin cancer isn’t discussed as much as carcinomas because it isn’t as common. Melanomas make up less than five percent of all skin cancers.
Melanoma occurs when there is DNA damage due to ultraviolet radiation that triggers mutation sin melanocytes. Melanocytes are skin cells that produce melanin when the skin is exposed to IV radiation. Treatment for melanoma varies throughout the different stages. In the early stages, it can be treated with surgery where the melanoma is removed. Towards the later stages, an attempt to remove the melanoma can be made along with targeted drug therapy and use of immunotherapy. The immunotherapy drugs are called checkpoint inhibitors such as pembrolizumab and nivolumab. These drugs are generally the first drugs used because they have the capability to shrink tumors in certain patients for long periods of time.
Ipilimumab is another checkpoint inhibitor that is usually not a drug used as first line treatment. It sometimes be used in combination with pembrolizumab or nivolumab. Due to the risk of serious side effects, this combination should be carefully considered.
The New England Journal of Medicine has an article based on a study comparing the efficacy of ipilimumab and nivolumab combination compared to the drugs being used alone in melanoma. In this study, the primary endpoints were progression-free survival and overall survival between the groups. There were three study groups comprised of 945 patients with previously untreated advanced melanoma were randomized 1:1:1 to receive nivolumab plus ipilimumab, nivolumab plus placebo, and ipilimumab plus placebo. All the patients in this study had unresectable or metastatic histologically confirmed stage III or stage IV melanoma. The efficacy endpoints were based on the intention-to-treat population. At 60 months, they followed up to assess overall survival, progression-free survival, and the objective response rate at the 95% CI were performed. They found that overall survival was longer in the two nivolumab containing groups compared to the ipilimumab group. The overall survival at 5 years was 52% in the combination group, 44% in the nivolumab group, and 26% in the ipilimumab group. The median progression-free survival was 11.5 months in the combination group, 6.9 months in the nivolumab group, and 2.9 months in the ipilimumab group. In terms of safety, the combination group had the highest adverse event occurrence at 59%. 23% of the patients in the nivolumab group reported side effects. 28% of patients in the ipilimumab group reported side effects. Based on the results of this study, it was found that patients taking both ipilimumab and nivolumab had sustained long-term overall survival at 5 years as compared to patients taking only ipilimumab and only nivolumab. This study probably helped progress the guidelines in using these immunotherapy drugs in the treatment of melanoma. Now, it is possible to see ipilimumab and nivolumab be used in the same treatment regimen for melanoma. The study also confirmed the worse safety profile in the combination group compared to using the drugs individually, which should be carefully taken into consideration when treating melanoma.
References:
1. Larkin J, Chiarion-Sileni V, Gonzalez R, Grob JJ, Rutkowski P, Lao CD, Cowey CL, Schadendorf D, Wagstaff J, Dummer R, Ferrucci PF, Smylie M, Hogg D, Hill A, Márquez-Rodas I, Haanen J, Guidoboni M, Maio M, Schöffski P, Carlino MS, Lebbé C, McArthur G, Ascierto PA, Daniels GA, Long GV, Bastholt L, Rizzo JI, Balogh A, Moshyk A, Hodi FS, Wolchok JD. Five-Year Survival with Combined Nivolumab and Ipilimumab in Advanced Melanoma. N Engl J Med. 2019 Oct 17;381(16):1535-1546. doi: 10.1056/NEJMoa1910836. Epub 2019 Sep 28. PMID: 31562797.
2. “Treatment of Melanoma by Stage.” American Cancer Society, https://www.cancer.org/cancer/melanoma-skin-cancer/treating/by-stage.html.
Cemiplimab & CSCC
Cutaneous squamous-cell carcinoma (CSCC) continues to be the second most prominent skin cancer in the world, second only to basal-cell carcinoma. Many skin cancers can go undetected for years, allowing it to spread without notice and become more deadly than if caught early. The cancer becomes metastatic, spreading to different parts of the body and may no longer be susceptible to surgery or chemotherapy. Immunotherapy is an area of cancer treatment that has been more frequently used in patients in whom surgery or radiation therapy are no longer options. In many treatment regimens, we can see immunotherapy as first-line, adjunct to other therapies, or used alone when there are not many options left. An important aspect of immunotherapy is ensuring that the drug of choice will influence the tumor. Tumors become highly mutated as they grow in the body, and skin tumors even more so because of the exposure to chronic ultraviolet light. These highly mutated tumors will likely show a positive response to immunotherapy that have a checkpoint inhibition.
Cemiplimab is a monoclonal antibody that is targeted against immuno-checkpoint programmed cell death-1 (PD-1) receptors that are expressed on tumors. Its ligand, PD-L1, is expressed on antigen presenting cells, mesenchymal stem calls, mast cells, and other cells of the host immune system. PD-L1 is also expressed on tumor cells. Tumor cells that have a higher expression of PD-L1 suppress signaling pathways that are involved in T-cell activation, which allows the tumor to evade death by the host immune system. Immunotherapies that target this PD-1/PD-L1 pathway have been shown to have better therapeutic effects on tumors that express this immune checkpoint.
Before the approval of cemiplimab, there were no systemic therapies available to treat advanced cutaneous squamous cell carcinoma. Approval of cemiplimab was based on two clinical trials that assessed a durable objective response rate from a multi-center, dose-finding trial, on patients with different types of advanced tumors. Patients were enrolled in the trial regardless of prior treatment, but only if surgery or radiation were no longer recommended. The objective response rate (ORR) evaluated using the Response Evaluation Criteria in Solid Tumors (RECIST) criteria and an additional assessment using digital photography for patients with locally advanced tumors were used. Results of the studies show that among 108 patients with advanced disease (75 with metastatic disease and 33 with locally advanced) disease, the ORR was 47% (95% CI: 38, 57) with 4% complete and 44% partial response rates. For the 75 patients with metastatic disease, the ORR was 47% (95% CI: 35, 59) and 49% (95% CI: 31, 67) for the 33 with locally advanced disease.
Like most immunotherapy, the safety data includes serious immune mediated adverse reactions including pneumonitis, hepatitis, colitis, diabetes mellitus, and nephritis. Among patients with advanced cutaneous squamous cell carcinoma, cemiplimab produced a positive response in about half of the patients with a similar safety profile to other immunotherapy the work with the PD-1/PD-L1 pathway. Since its initial approval in 2018, the indications for cemiplimab have been expanded to include basal cell carcinoma and non-small cell lung cancer.
References:
1. Ahmed SR, Petersen E, Patel R, Migden MR. Cemiplimab-rwlc as first and only treatment for advanced cutaneous squamous cell carcinoma. Expert Rev Clin Pharmacol. 2019;12(10):947-951. doi:10.1080/17512433.2019.1665026
2. Zheng Y, Fang YC, Li J. PD-L1 expression levels on tumor cells affect their immunosuppressive activity. Oncol Lett. 2019;18(5):5399-5407. doi:10.3892/ol.2019.10903
3. Center for Drug Evaluation and Research. Cemiplimab-RWLC for cutaneous squamous cell carcinoma. U.S. Food and Drug Administration. https://www.fda.gov/drugs/drug-approvals-and-databases/fda-approves-cemiplimab-rwlc-metastatic-or-locally-advanced-cutaneous-squamous-cell-carcinoma. Accessed January 19, 2022.
Sunscreen
Written by: Hillary Pham and Jae Chang
Sunscreen has always been a recommended product to be used on individuals on a daily basis. Even when individuals do not plan to be outside, it is still recommended to wear sunscreen indoors. This is because UV rays can still emit indoors too, like at any openings such as a window. Health care providers over the years have promoted the use of sunscreen as it can cause serious health damages and conditions. Although sunlight is very vital for any individuals, it is also as important to wear sunscreen as well. Since, it is possible for any kind of sun rays to cause serious skin damages, such as skin cancer, due to the ultraviolet radiation of the sun.
UV rays can cause damaging effects on DNA. The association between UV rays and DNA is that UV rays can cause changes in the skin which causes actinic keratoses, a precursor of non-melanoma skin cancer (NMSC) and squamous cell carcinoma (SCC). It is said that NMSC is the most common type of malignancy in the United States. UV rays are categorized by either UVA and UVB, and while both types of UV rays are of concern, more attention is placed on UVA. NMSC and SCC are generally attributed to UVA radiation because UVA penetrates through the skin deeper than UVB. However, other factors including amount of sun exposure during childhood, genetic predisposition, pigmentation, and aging contribute to the risk for developing skin cancer.
To briefly explain the mechanism of UV rays that cause damage, UVA radiation exposure causes the formation of reactive oxygen species. The reactive oxygen species then damages DNA by breaking the tertiary structure of DNA. UVB is absorbed by DNA to cause similar structural damage. Furthermore, mutations in p53 tumor suppressor gene which is involved with DNA repair and apoptosis in cells with sustained DNA damage caused by UV ray exposure is associated with DNA damaging and skin malignancy development.
There are many sunscreens on the market. So, how do individuals know which to choose from? Sunscreen efficacy is based on a factor called the sun protection factor, or as most people know, SPF. For a long time, researchers and scientists have known that sunscreen is effective and beneficial to use. However, there is still an ongoing debate on what the precise SPF value is the absolute best to use. Nevertheless, the recommended range for SPF value is anywhere from 15 to 30, that studies have shown.
Studies have found that SPF only refers to the ability to protect the skin against sunburn and is unrelated to reducing the risk for skin cancer. Sunburn is caused by the skin’s exposure to sunlight, in particular, UVB. Therefore, the SPF portion of sunscreen is only meant for skin protection against sunburn and not the risk of developing skin cancer from UVA and UVB. Furthermore, SPF does not include protection against UVA. A study conducted by Poon and colleagues has demonstrated that immune protection factor or IPF was a better predictor of protection against UVA than SPF. Nevertheless, general studies all agree that broad spectrum sunscreens can decrease the rate of new precancerous lesions, which leads to less actinic keratoses and therefore fewer SCC. Unfortunately, there is little evidence of sunscreens protecting against basal cell skin cancers and melanomas.
In regard to application of the products, some scientists have argued that the sunscreen should be reapplied every 2 to 3 hours after the initial application. However, studies done by Diffey, et. al shows that “typically reapplication of sunscreen at 20 minutes results in 60% to 85% of the UV exposure if sunscreen were reapplied at 2 hours.” So, in conclusion, Diffey states that sunscreen should be first applied 15 to 30 minutes before going outside in any areas of the body that may be exposed to the sunlight. Then, to repeat the application again, after 15 to 30 minutes. And of course, after that any reapplication should be considered depending on what the individual may be doing or how long the individual is outside in the sun for.
Overall, there is still ongoing talk and research about the best SPF reapplication time period is between numerous researchers. Nevertheless, if there is one thing that all researchers, scientists, and providers can all agree on, it is that every individual should wear sunscreen every single day, no matter what their day may look like.
References:
Diffey, B. L. (2001). When should sunscreen be reapplied?. Journal of the American Academy of Dermatology, 45(6), 882-885.
Gasparro, F. P., Mitchnick, M., & Nash, J. F. (1998). A review of sunscreen safety and efficacy. Photochemistry and photobiology, 68(3), 243-256.
Raffa RB, Pergolizzi JV Jr, Taylor R Jr, Kitzen JM; NEMA Research Group. Sunscreen bans: Coral reefs and skin cancer. J Clin Pharm Ther. 2019 Feb;44(1):134-139. doi: 10.1111/jcpt.12778. Epub 2018 Nov 28. PMID: 30484882.
Natalie Eshaghian & Donna Salib
Sunscreens and Skin Cancer
Our skin is the largest organ of our bodies, however, it is also one of the most sensitive as well. Our skin is directly affected by the environment unlike the other organs in our body.1 Skin cancer is one of the most prominent cancers in the United States. There are different types of skin cancers ranging from non-melanoma skin cancers to melanoma which is the most severe form. Skin cancer is on the rise, where approximately 5 million people a year are diagnosed with skin cancer, so it is important to protect ourselves from the disease.2 There are multiple different risk factors for skin cancer, but the most predominant would be UV radiation. Although our bodies need natural UV radiation as a source of vitamins, excessive exposure is seen to deteriorate our skin and make it more susceptible to cancer.
There are two different UV radiations that are seen to be associated with skin cancer, UVA and UVB. UVA is seen to cause skin aging due to its long wavelength, and is seen in the use of tanning beds, whereas UVB causes skin burning because of its shorter wavelength. UVA is more harmful than UVB due to its longer wavelength and reaches deeper into the skin layers.3 Although UV radiation is one of the main causes of skin cancer, it is also one of the most important modifiable risk factors, meaning that it is a risk that can be easily prevented if changed.4 In the epidermis, there are cells called melanocytes and they release a dark pigment, known as melanin, when the skin cells are damaged by UV. Melanin is able to absorb UV light, acting as a UV shield, but melanin isn't able to completely prevent skin damage from UVB. Essentially, the melanin can begin to absorb the UV light and cause damaging effects to the skin.5 Many people with darker skin tones believe that they are void of developing skin cancers, however, it is still very possible to develop skin cancer in both light and dark skin tones due to excessive UV exposure.
There are 3 major types of skin cancer: basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), which are both classified as non-melanoma skin cancer, and melanoma.6 Basal cell carcinoma usually develops in areas of the body that was exposed to the sun, such as the face, however, the cancer cells grow slowly making it unlikely to become life-threatening. Squamous cell carcinoma also usually occurs in sun-exposed areas of the body, such as the face and hands, however, this type is more likely to spread. Melanomas are the most aggressive type of skin cancer and can develop anywhere on the body. Melanomas can develop in existing benign moles that become cancerous and can be cured if detected and treated early. If left untreated, melanomas can eventually lead to death. Studies have shown a significant decrease in incidences of squamous cell carcinomas and a reduced risk in invasive melanomas in people who use sunscreen daily.7
It is important to protect our skin from the excessive harmful effects of UV radiation. Some ways to protect oneself is using sunscreen with a sun protective factor (SPF) of 15 or higher. It is important to learn how to read sunscreen labels to know which is properly protecting your skin and which is not. Sunscreens are categorized as physical and chemical blockers.8 Sunscreen can either absorb or reflect UV photons before they reach our skin. Sunscreens that are considered physical blockers are those that act as a shield and deflect UV rays away from the skin. It usually contains two active mineral ingredients: zinc oxide and titanium oxide, which are the only two ingredients that have been labeled safe by the FDA. Recently, certain sunscreen brands and products were recalled because they contain a harmful chemical known as benzene, which is found to be carcinogenic. According to Johnson & Johnson, benzenes are found in many of our daily exposures, but it is a potential cancer causing substance, also known as a human carcinogen, depending on the level and extent of exposure.9 The very product we use to protect our skin from the harmful UV rays to prevent skin cancers is seen to be the source of causing cancers. It is important to distinguish the proper sunscreens to use with the correct ingredients to protect you from all types of harm.
Physical sunscreens that protect against both UVB and UVA are also labeled broad-spectrum. Chemical sunscreens absorb the UV rays and convert them into heat which is then released. Chemical sunscreens are not as long lasting as physical sunscreens, therefore it has to be frequently applied throughout the day and takes longer to work ranging from 30 minutes to 50 minutes compared to physical sunscreens which come into action instantly. According to the American Academy of Dermatology, it is recommended to choose a sunscreen that protects against both UVA and UVB with an SPF of either 30 or 50 depending on the weather.10 The sun protective factor (SPF) is determined by calculating the number of seconds it takes for the skin to be exposed. For example, if it normally takes about 10 minutes in the sun for a person’s skin to get burned without sunscreen, then theoretically if they were to use SPF 30, the sunscreen should last them 50 times as long, about 500 minutes. Nevertheless, the sunscreen should still be applied frequently about every 2 hours. In addition to sunscreens, a person can use protective clothing, such as long sleeves and pants, hats, etc. to shield themselves from the UV light, as well as simply staying out of the sun, especially when the sun’s rays are strongest between 10 a.m. and 4 p.m.2 Although people love to tan and stay in the sun during the sunny summer days, they could use these methods to help protect themselves and lower their risk of developing skin cancer. Sunscreen does not stop a person from getting that glowing tan, but will protect them from absorbing the harmful UV rays.
Cancer doesn’t discriminate, so it is important to note that all types of people can develop skin cancer due to excessive sun exposure, and we all need to protect ourselves from it. Furthermore, our body is delicate and it is important to protect ourselves from different forms of harm, such as chemicals as well as environmental conditions. As pharmacists, we need to educate the public on proper sun exposure and how to protect ourselves. Certain things like sunscreens are important to note and help a consumer read a label to ensure they are receiving the correct protection, as well as free of any other harmful chemicals, such as benzene. The sun may be our friend, but it can always turn on us. Skin-aging and non-melanoma skin cancers are largely preventable and it is our priority to help the world as a whole to educate on sun safety and protection.
References:
1 Rittié L, Fisher GJ. Natural and sun-induced aging of human skin. Cold Spring Harb Perspect Med. 2015;5(1):a015370. Published 2015 Jan 5. doi:10.1101/cshperspect.a015370
https://www-ncbi-nlm-nih-gov.jerome.stjohns.edu/pmc/articles/PMC4292080/
2 Watson M, Holman DM, Maguire-Eisen M. Ultraviolet Radiation Exposure and Its Impact on Skin Cancer Risk. Semin Oncol Nurs. 2016;32(3):241-254. doi:10.1016/j.soncn.2016.05.005
https://www-ncbi-nlm-nih-gov.jerome.stjohns.edu/pmc/articles/PMC5036351/
3 UV Radiation. The Skin Cancer Foundation. (2021, May 27). https://www.skincancer.org/risk-factors/uv-radiation/
4 D'Orazio J, Jarrett S, Amaro-Ortiz A, Scott T. UV radiation and the skin. Int J Mol Sci. 2013;14(6):12222-12248. Published 2013 Jun 7. doi:10.3390/ijms140612222 https://www-ncbi-nlm-nih-gov.jerome.stjohns.edu/pmc/articles/PMC3709783/
5Brenner M, Hearing VJ. The protective role of melanin against UV damage in human skin. Photochem Photobiol. 2008;84(3):539-549. doi:10.1111/j.1751-1097.2007.00226.x
6Nakayama K. Growth and progression of melanoma and non-melanoma skin cancers regulated by ubiquitination. Pigment Cell Melanoma Res. 2010;23(3):338-351. doi:10.1111/j.1755-148X.2010.00692.x
7 Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020;192(50):E1802-E1808. doi:10.1503/cmaj.201085
https://www-ncbi-nlm-nih-gov.jerome.stjohns.edu/pmc/articles/PMC7759112/
8 Latha MS, Martis J, Shobha V, et al. Sunscreening agents: a review. J Clin Aesthet Dermatol. 2013;6(1):16-26.
9 Johnson & Johnson. Content Lab U.S. 14th July,2021. Available at: https://www.jnj.com/johnson-johnson-consumer-inc-issues-voluntary-recall-of-specific-neutrogena-and-aveeno-aerosol-sunscreen-products-due-to-the-presence-of-benzene.
10 How to select a sunscreen. American Academy of Dermatology. Date Accessed: 23 July,2021 http://www.aad.org/public/spot-skin-cancer/learn-about-skin-cancer/prevent/how-to-select-a-sunscreen.
Sunscreen! Sunscreen! Sunscreen! Have you ever watched a dermatologist go through their skin care routine and not mention sunscreen? No? Me neither! One product that dermatologists unanimously agree on its importance is… you have guessed it! Sunscreen! Sunscreen provides many benefits for the skin starting with decreasing your risk of developing skin cancer. It also has anti-aging benefits as well as aiding in an even skin tone. Sunscreen helps against the damage that the sun can cause onto the skin. Skin cancer is when the outermost layer of the skin, the epidermis, is damaged due to DNA mutation. This leads to an abnormal cell growth in the epidermis. There are four different types of skin cancer that can occur; they are basal cell carcinoma (BCC), squamous cell carcinoma (SCC), melanoma, and Merkle cell carcinoma. Skin cancer mainly occurs from the harmful ultraviolet (UV) rays of the sun as well as the UV used in tanning beds.
The truth is, the word cancer on its own sounds very scary. It has a very negative connotation to it since most times people hear the words cancer then it is assumed to be associated with bad news. When it comes to skin cancer, if it is caught early then there is a great chance of eliminating the cancer before it spreads. Here is what you need to know about the different kinds of skin cancer. BCC is the most common type of skin cancer that occurs in the epidermis. It often develops in areas exposed to the sun such as the face, neck, shoulders, and back. If BCC is caught and treated early, it can be only cause destruction locally but rarely do these cancers spread to other parts of the body and become fatal. The second most common type of skin cancer is SCC. Just like BCC, SCC also occurs in the epidermis and often develops in areas that are exposed to the sun often such as face, neck, and hands and the skin is shown to have signs of sun damage such as wrinkles and age spots. If SCC is not detected and treated early then it can at times grow rapidly and spread which can be fatal. Melanoma is another type of skin cancer that develops from skin cells that produce melanin. Melanin is what gives us our skin color.
Melanoma often appears as a mole and it can be anywhere in the body not necessarily due to exposure to the sun. It can be also caused by tanning beds. It is one of the more rare and dangerous types of skin cancer but it is also curable if it is caught and treated early. Lastly, Merkel cell carcinoma (MCC) is the rarest type of skin cancer and it is very aggressive. It can appear as a painless tumor on an area of the body that is exposed to the sun but there is a high chance of it recurring and spreading throughout the body. Just like other types of cancer, early detection and treatment in crucial especially with MCC.
After learning about the different kinds of skin cancer, it is important to not only apply sunscreen but to understand how to apply it as well as the type of sunscreen that needs to be applied. Sunscreen comes with different protection factors. You may have heard and seen products that have SPF 15, SPF 30, SPF 50, etc. on it but what is the difference between each? Is there really a difference? SPF 15 helps protect against 93% of the UV rays of the sun and SPF 30 helps protect against 97% while SPF 50 protects against 98% of the sun rays. Any SPF that is higher than SPF 50 can protect more against the UV rays but it is an insignificant increase. It is recommended to use SPF 30 or more especially when spending a day outdoors.
Everyone should wear sunscreen daily and should apply it 30 minutes before going outdoors. Reapplication every 2 hours is crucial. There are different types of sunscreens that are present such as physical and chemical sunscreens. Physical sunscreens include ingredients such as zinc oxide and titanium dioxide and may cause less skin irritation than chemical sunscreens but nonetheless both types are safe to be used to protect against UV rays. Sunscreen is a great way to protect yourself against harmful UV rays but it is not completely effective on its own. Wearing long-sleeves, tight clothes, wide-brimmed hat and sunglasses as well as staying in the shade are additional ways that you can protect yourself against harmful UV rays. Stay safe!
Center, John Stoddard Cancer. “8 Reasons to Wear Sunscreen This Summer.” 8 Reasons to Wear Sunscreen | John Stoddard Cancer Center, 27 May 2020, www.unitypoint.org/desmoines/article.aspx?id=e0a22a4f-77c7-4a9a-b779-ed3c37956982.
“Skin Cancer Information.” The Skin Cancer Foundation, 1 June 2021, www.skincancer.org/skin-cancer-information/.
“Sunscreen.” The Skin Cancer Foundation, 28 May 2021, www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/.
Sunscreen will protect the skin against UVA/UVB rays produced by the sun, UV radiation is carcinogenic meaning it is a cause of skin cancer as well as premature skin aging, sunburns and cataracts. Ultraviolet A (UVA) has a longer wavelength and is able to enter the skin barrier leading to premature skin aging. Ultraviolet B (UVB) has a shorter wavelength and will damage the surface of the skin barrier leading to sunburns. Prolonged, unprotected sun exposure to UVB rays will lead to skin cancer more commonly squamous cell carcinoma (SCC), malignant melanoma and basal cell carcinoma (BCC).
Malignant melanoma is the deadliest form of skin cancer, where epidermal melanocytes are affected. Most melanomas are linked to pre-existing moles that a person may have and if it is caught in its early stages it can be surgically removed. BCC and SCC are non-melanomatous skin cancers that affect the epidermal keratinocytes, BCC and SCC are less deadly since they remain localized in the primary affected area. Treatment includes microsurgery, cryosurgery, resection and MOHS.
UV rays will generate reactive oxidative species (ROS) such as hydroxyl radical, superoxide anion, and hydrogen peroxide producing DNA mutations. ROS will cause free radical injury to nucleotide bases which will lead to mutagenesis, for example oxidative change may mutate a G/C pair to A/T pair. Mutations resulting from oxidative mutagenesis are found in tumors isolated from the skin leading to production of carcinogens. UV radiation directly affects nucleotide base pairing in DNA, pyrimidine bases are most susceptible to DNA mutation due to their UV absorption. UV radiation will lead to photo lesions that block DNA replication, impairs transcription and cause abnormal base pairings. UV induced DNA mutations are a major cause of melanomas and other skin cancers, due to the direct mutagenic role of UV radiation.
Sunscreens are vital to sun damage and skin cancer prevention. The two main categories of sunscreens are physical and chemical sunscreens, and come in a variety of forms including sunscreen sticks, oils, creams, liquids, sprays, and gels. Physical sunscreens are also known as mineral sunscreens and contain minerals for example zinc oxide or titanium dioxide. Physical sunscreens will reflect and scatter UVA/UVB rays before the rays entering the skin. Physical sunscreens are generally non-skin irritating and not known to cause many allergic reactions.
Chemical sunscreens contain UVA-absorbing ingredients such as avobenzone/benzophenone as well as UVB-absorbing ingredients. Sunscreens containing para-aminobenzoic acid (PABA) and benzophenone will cause skin reactions such as skin rashes, burning, blisters, redness and itchiness. However many chemical sunscreens have advantages in broader-spectrum coverage against solar radiation, meaning they’ll provide coverage against both UVA and UVB rays.
SPF found in sunscreens stands for sun protection factor, according to the FDA it is a measurement of how much UV radiation is needed to cause sunburns when using sunscreen. The higher the SPF content the longer the sun protection lasts, however the Skin Cancer Foundation recommends using a water-resistant broad spectrum sunscreen with minimum SPF of 30 when outdoors but if one is mostly indoors then SPF of 15 is fine. SPF is often included in other skincare and makeup products, for example some moisturizers, foundations, face powders, even lip balms will contain SPF.
Everyone requires sunscreen year round throughout all four seasons, and it is recommended to apply sunscreen thirty minutes prior to going outside with a re-application every two hours. Also sunscreen application should not only be limited to the face, the body should get a coverage of sunscreen as well. There are a range of sunscreens specifically formulated for the face or body available over the counter. For the ultimate skin protection, one must implement additional skin protection measures. Limit sun exposure as much as possible and avoid tanning beds because they also emit UV radiation also linked to skin cancer.
D'Orazio J, Jarrett S, Amaro-Ortiz A, Scott T. UV radiation and the skin. Int J Mol Sci. 2013;14(6):12222-12248. Published 2013 Jun 7.
Latha MS, Martis J, Shobha V, et al. Sunscreening agents: a review. J Clin Aesthet Dermatol. 2013;6(1):16-26.
Skin Cancer Foundation. All About Sunscreen. Updated 2021 January. Accessed 2021 May 24. https://www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/
Skin Cancer Foundation. Ask the Expert: Does a High SPF Protect my Skin better? Published 2020 June 9. Accessed 2021 May 24. https://www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/
Sunscreen: The Burning Facts. Environmental Protection Agency. Published 2006 September. Accessed 2021 May 24. Pages 1-6.
Food and Drug Administration. Sun Protection Factor (SPF). Updated 2017 July 14. Accessed 2021 May 24. https://www.fda.gov/about-fda/center-drug-evaluation-and-research-cder/sun-protection-factor-spf
Bottom line - everyone should use a broad-spectrum sunscreen with an SPF of 15 or more. (specifically SPF 15 for daily use versus SPF 30+ for extended outdoor activities like a beach trip or hiking trip). Sunscreen includes active ingredients that help prevent the sun’s UV radiation from reaching your skin. There are two broad categories that we can distinguish sunscreen into: physical and chemical sunscreens. Physical sunscreen ingredients block and scatter the rays before the penetrate your skin. Examples of these would be minerals like titanium dioxide and zinc oxide. Chemical sunscreen ingredients absorb the UV rays before they can damage your skin. Examples of these would be avobenzone and octisalate. It is important to note that the sunscreens that are labeled as organic or natural are essentially the same as others that are not. As noted by source 3, it is simply terms used as a marketing strategy. All active ingredients in sunscreens are chemically derived.
People often believe that the higher the SPF, the better the sunscreen. However, this is not true. SPF stands for Sun Protection Factor. This number tells us how long the sun’s UVB rays would take to redden your skin if you were to apply the sunscreen exactly as directed, compared to the amount of time without the sunscreen. Therefore, using an SPF 30 sunscreen would take you 30 times longer to burn than if you did not use the sunscreen.
Source 2 summarizes that sunscreens should not be the first or sole agent used for skin cancer prevention, but should be used in conjunction with clothing to prevent overexposure. There are indications that childhood sun exposure may be particularly important in the generation of basal cell carcinoma and melanoma later in life.
1. Use of sunscreen and risk of melanoma and non-melanoma skin cancer: a systematic review and meta-analysis, https://pubmed.ncbi.nlm.nih.gov/29620003/
2. Sunscreens in melanoma and skin cancer prevention, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1180647/
https://www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/
Bottom line - everyone should use a broad-spectrum sunscreen with an SPF of 15 or more. (specifically SPF 15 for daily use versus SPF 30+ for extended outdoor activities like a beach trip or hiking trip). Sunscreen includes active ingredients that help prevent the sun’s UV radiation from reaching your skin. There are two broad categories that we can distinguish sunscreen into: physical and chemical sunscreens. Physical sunscreen ingredients block and scatter the rays before the penetrate your skin. Examples of these would be minerals like titanium dioxide and zinc oxide. Chemical sunscreen ingredients absorb the UV rays before they can damage your skin. Examples of these would be avobenzone and octisalate. It is important to note that the sunscreens that are labeled as organic or natural are essentially the same as others that are not. As noted by source 3, it is simply terms used as a marketing strategy. All active ingredients in sunscreens are chemically derived.
People often believe that the higher the SPF, the better the sunscreen. However, this is not true. SPF stands for Sun Protection Factor. This number tells us how long the sun’s UVB rays would take to redden your skin if you were to apply the sunscreen exactly as directed, compared to the amount of time without the sunscreen. Therefore, using an SPF 30 sunscreen would take you 30 times longer to burn than if you did not use the sunscreen.
Source 2 summarizes that sunscreens should not be the first or sole agent used for skin cancer prevention, but should be used in conjunction with clothing to prevent overexposure. There are indications that childhood sun exposure may be particularly important in the generation of basal cell carcinoma and melanoma later in life.
1. Use of sunscreen and risk of melanoma and non-melanoma skin cancer: a systematic review and meta-analysis, https://pubmed.ncbi.nlm.nih.gov/29620003/
2. Sunscreens in melanoma and skin cancer prevention, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1180647/
https://www.skincancer.org/skin-cancer-prevention/sun-protection/sunscreen/