Vol. 64, No. 47
December 4, 2015
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CDC Grand Rounds: Prevention and Control of Skin Cancer
This is another in a series of occasional MMWR reports titled CDC Grand Rounds. These reports are based on grand rounds presentations at CDC on high-profile issues in public health science, practice, and policy. Information about CDC Grand Rounds is available at http://www.cdc.gov/about/grand-rounds.
WeeklyDecember 4, 2015 / 64(47);1312-4
1; , MSPH1; , PhD1; 2; , MD3; , MSN4; , MD4; , MD5, MPH
Skin cancer is the most common cancer in the United States, and most cases are preventable (1). Persons with certain genetic risk factors, including having a lighter natural skin color; blue or green eyes; red or blonde hair; dysplastic nevi or a large number of common moles; and skin that burns, freckles, or reddens easily or becomes painful after time in the sun, have increased risk for skin cancer (1). Persons with a family or personal history of skin cancer, especially melanoma, are also at increased risk. Although these genetic factors contribute to individual risk, most skin cancers are also strongly associated with ultraviolet (UV) radiation exposure. Most UV exposure comes from the sun, although some persons use UV-emitting indoor tanning devices (e.g., beds, booths, and lamps).
The three most common types of skin cancer, in descending order, are basal cell carcinoma, squamous cell carcinoma, and melanoma (1). Basal cell carcinoma alone is thought to be more common than any other cancer, but central cancer registries* (CCRs) do not collect data on basal cell carcinoma, so incidence is unknown. Squamous cell carcinoma is less common than basal cell carcinoma and can cause death, although most cases are treatable. Melanoma is the least common of the three main types of skin cancer, but causes the most deaths. In 2012, CCRs in the United States reported approximately 67,000 new melanoma cases and 9,000 deaths from melanoma (2).
Overall, rates of melanoma incidence are approximately 60% higher among men than women (25.5 and 15.9 per 100,000, respectively, in 2012), and rates increase rapidly after age 50 years. However, among persons aged <50 years, melanoma is more common among women (2).
Rates of skin cancer have tripled since the early 1970s. Although much of the increase has been among early stage cancers, and mortality has remained relatively stable, more recent analyses have found increases among later stage cancers, and mortality rates for males have begun to increase (3).
Differences by race in skin cancer risk are largely related to differences in skin type and other genetic risk factors. The rate of melanoma in non-Hispanic whites (whites) is approximately 25 times higher than the rate in blacks and six times higher than the rate in Hispanics. However, a diagnosis of melanoma in blacks and Hispanics often occurs later than in whites, which has led to poorer survival rates (1).
The causal relationship between UV exposure and skin cancer among populations with comparatively more sun-sensitive skin is well established, and recent genetic research has found a UV exposure signature among mutations specific to melanoma (4). However, 37% of persons in the United States report getting sunburned each year, with the highest rate (65%) among white adults aged <30 years (5). Among persons reporting sunburn, 12% report four or more burns during the past year (5). Approximately 67% of men and 73% of women report using at least one method of sun protection when outdoors for >1 hour on a sunny day (6). However, use of each individual method of protection (e.g., sunscreen, hats, shade, and protective clothing) is substantially lower, especially among men. For example, only 21% of men and 41% of women report wearing sunscreen when outdoors for >1 hour on a sunny day. Although women tend to report higher rates of sun protection, intentional UV exposures, including sunbathing and indoor tanning, are more common among younger women than men (1). Only 10% of high school students report wearing sunscreen when outdoors for >1 hour on a sunny day (7). An estimated 11.6 million persons in the United States, including almost one in three white women aged 16–25 years, tan indoors each year (8–10). The U.S. Food and Drug Administration (FDA) recently reclassified tanning devices to better reflect their risk level, and requires that devices include warnings stating that their use is contraindicated for persons aged <18 years (11).
Evidence-Based Skin Cancer Prevention
Many skin cancers can be prevented by the strategies promulgated in the Surgeon General's Call to Action to Prevent Skin Cancer (Call to Action) (1):
Increase opportunities for sun protection in outdoor settings. Increasing shade and other opportunities for sun protection in outdoor recreational settings like parks, sports arenas, pools, beaches, and ski resorts can help reduce UV overexposure and support individual sun protection behaviors. Likewise, efforts to increase shade and provide support for other methods of sun protection in schools and occupational settings are important, especially for recess and other outdoor school activity areas and for outdoor work environments.
Provide individuals with the information they need to make informed, healthy choices about UV exposure. The general public often does not understand the widely available information on the UV Index.† Effective messages with prompts on using sun protection when the UV Index is high might help increase use of sun protection at schools and in occupational settings. The U.S. Preventive Services Task Force recommends counseling children, adolescents, and young adults aged 10–24 years who have fair skin about minimizing their exposure to UV to reduce risk for skin cancer.§ Aligning sun protection messages with other physical activity and outdoor recreation messages, such as reminders to wear wide-brimmed hats when walking or to reapply sunscreen during water breaks, might provide an opportunity to address multiple important public health goals.
Promote policies that advance the national goal of preventing skin cancer. Policies at all levels, including federal, state, local, and institutional policies in workplaces, schools, and businesses, can help support skin cancer prevention. School policies that prohibit hats or student possession of sunscreen can create barriers to the use of these important sun protection methods. School and workplace policies that support sun protection include education on UV exposure, providing shade at school or work, and encouraging students and employees to use sun protection. Organizational or municipal shade policies can require the provision of shade when constructing or refurbishing public facilities or schools, thereby increasing the availability of shade (1,12).
Reduce harms from indoor tanning. UV from indoor tanning devices has been classified by the World Health Organization and the U.S. Department of Health and Human Services as a known human carcinogen. Federal, state, and local regulations have recently increased; 13 states, the District of Columbia, and several cities and counties have now banned the use of indoor tanning beds for persons aged <18 years (13); however, tanning is particularly common among young adult white women and in areas near college campuses. The availability of tanning devices in less-regulated settings, such as homes, gyms, and apartment building common areas, can pose unique challenges for enforcing regulations.
Strengthen research, surveillance, monitoring, and evaluation related to skin cancer prevention. A better understanding of the role of UV exposure in skin cancer and evaluation of interventions to reduce overexposure to UV can help inform future prevention efforts. Although providers are required to report melanomas to CCRs, many in situ and early stage invasive melanomas are diagnosed and treated in outpatient settings, which often lack the reporting infrastructure found in hospital settings (1). Developing methods to better measure the prevalence of basal cell carcinoma and squamous cell carcinoma could also provide important information to measure the impact of public health efforts.
Implementation and Impact of Prevention Strategies
The Call to Action names various sectors as partners in prevention: policymakers; businesses and employers; health care systems, insurers, and clinicians; early learning centers, schools, colleges, and universities; community, nonprofit, and faith-based organizations; and persons and families (1). Some partners, such as the Arizona Department of Health Services and The University of Texas MD Anderson Cancer Center (MD Anderson), have implemented some of the prevention strategies named in the Call to Action through their previous and current work; other partners implemented these strategies after the release of the Call to Action.
The state of Arizona names sun safety as a top public health priority, and its previous and current work has addressed several of the Call to Action strategies. The SunWise program, developed by the U.S. Environmental Protection Agency and now supported by the National Environmental Education Foundation, is a health and environmental education program that teaches children how to protect themselves from overexposure to the sun (14). Beginning in 2005, Arizona state law has required that the SunWise program be incorporated as part of school education curricula for public school students in kindergarten through 8th grade (K–8). Recently, Arizona expanded the requirement to include state-licensed early learning center providers, and the requirement could be voluntarily adopted by private schools or by organizations such as sports teams and summer camps. Educators in Arizona's K–8 schools have access to school policy template language to make it easier to implement sun safety practices. Arizona officials are also working to improve melanoma reporting to the state's CCR.
A multidisciplinary team at MD Anderson is focusing on melanoma treatment and prevention through a program called the "Melanoma Moon Shot" that seeks to accelerate the pace that scientific discoveries are converted into clinical practices (http://www.cancermoonshots.org/cancer-types/melanoma). Studies of melanoma cancer genes are providing more information on the etiology and clinical behavior of melanoma, with the goal of increasing long-term survival rates and improving the antitumor immune response. Researchers are also investigating interventions to increase sun protective behaviors in children (e.g., Ray and the Sunbeatables: A Sun Safety Curriculum for Preschoolers) (15), and to use appearance-focused interventions (e.g., highlighting UV-related skin damage) to impact tanning behaviors and attitudes in middle school students. MD Anderson served as an important resource for educating the Texas legislature on the risks of indoor tanning and sunscreen use in schools. In 2013, Texas passed legislation that prohibits the use of indoor tanning facilities by persons aged <18 years (16), and in June 2015, the state passed legislation that permits public school students to "possess and use a topical sunscreen product while on school property or at a school-related event or activity to avoid overexposure to the sun ... if the product is approved by the federal Food and Drug Administration for over-the-counter sunscreen products use" (17).
Cities have also been active in developing easy-to-implement sun-safe practices. The city of Miami Beach, Florida, has collaborated with Miami Beach's Mount Sinai Hospital to provide 50 free sunscreen dispensers on beaches and in parks. The city of Boston, Massachusetts, has provided 30 free sunscreen dispensers in citywide parks in collaboration with nonprofit organizations. A goal of the city of Montclair, New Jersey, is to become the "sun-smartest city in America" by working to implement all of the strategies outlined in the Call to Action. Other parks and recreation resources are available athttp://www.cdc.gov/cancer/skin/pdf/skincancer_parks-recreation.pdf .
Future Impact of Prevention Efforts
In the United States, an estimated total of $8.1 billion is spent annually on treatment for all skin cancers combined, and costs have been increasing in recent years (18). Without communitywide intervention programs, the annual cost of treating newly diagnosed melanoma cases is estimated to increase approximately 250% from 2011–2030 (from $457 million to $1.6 billion) (19). However, comprehensive skin cancer prevention programs to reduce sun exposure, facilitate sun protection, prevent sunburn, and reduce indoor tanning can reduce future cases of skin cancer, and can be cost-effective. Prevention programs in Australia have been estimated to save AU$2.30 for every AU$1 invested (20). Implementation of communitywide programs in the United States has the potential to annually avert an estimated 230,000 melanoma cases and prevent $2.7 billion in costs for newly diagnosed melanomas (19).
1Division of Cancer Prevention, National Center for Chronic Disease Prevention and Health Promotion, CDC; 2Arizona SunWise Skin Cancer Prevention Program, Arizona Department of Health Services; 3The University of Texas MD Anderson Cancer Center, Houston, Texas; 4Office of the Associate Director for Science, CDC;5Office of the Surgeon General, U.S. Department of Health and Human Services.
Corresponding author: Meg Watson, MWatson2@cdc.gov, 770-488-3097.
* Central cancer registries collect detailed information on cancer patients from a defined geographic area or a specific population.
† The UV Index, developed by the National Weather Service and the U.S. Environmental Protection Agency, provides a daily forecast of the expected risk for overexposure to the sun. The index predicts UV radiation intensity levels on a scale of 1 to 11+, with 1 indicating a low risk for overexposure and 11+ signifying an extreme risk. Calculated on a next-day basis for every zip code across the United States, the UV Index takes into account clouds and other local conditions that affect the amount of UV radiation reaching the ground in different parts of the country.
§ More information available at http://www.uspreventiveservicestaskforce.org/Page/Document/UpdateSummaryFinal/skin-cancer-counseling.