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US Preventive Services Task Force. Guide to Clinical Preventive Services: Periodic Updates [Internet]. 3rd edition. Rockville (MD): Agency for Healthcare Research and Quality (US); 2002-.

  • This publication is provided for historical reference only and the information may be out of date.

This publication is provided for historical reference only and the information may be out of date.

Cover of Guide to Clinical Preventive Services

Guide to Clinical Preventive Services: Periodic Updates [Internet]. 3rd edition.

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Scientific Evidence

Epidemiology and Clinical Consequences

Melanoma is a leading cause of cancer death in the United States. The lifetime risk for dying of melanoma is 0.36 percent in white men and 0.21 percent in white women.3 Between 1973 and 1995, the age‐adjusted incidence of melanoma increased more than 100 percent, from 5.7 per 100,000 people to 13.3 per 100,000 people. The increase in annual incidence rates is likely due to several factors, including increased sun exposure and possibly earlier detection of melanoma. Although primary prevention efforts have focused on young people, the elderly (especially elderly men) bear a disproportionate burden of morbidity and mortality from melanoma and nonmelanoma skin cancer. Men older than age 65 account for 22 percent of the newly diagnosed cases of malignant melanoma each year and women in the same age group account for 14 percent. Basal cell and squamous cell carcinomas are more than 10 times as common as melanoma but account for less morbidity and mortality. Squamous cell cancers, however, may account for 20 percent of all deaths from skin cancer.

Effectiveness of Available Interventions

Preventive strategies include reducing sun exposure (e.g., by wearing protective clothing and using sunscreen regularly), avoiding sunlamps and tanning equipment, and practicing skin self‐examination. There is little direct evidence, however, that any of these interventions reduce skin cancer morbidity or mortality.

Reducing Sun Exposure

Avoiding direct sunlight by staying indoors or in the shade or by wearing protective clothing is the most effective measure for reducing exposure to ultraviolet light, but there are no randomized trials of sun avoidance to prevent skin cancer. In numerous observational studies, increased sun exposure in childhood and adolescence is associated with increased risk for non‐melanoma skin cancer, which usually occurs in sun‐exposed areas such as the face.

Recent studies provide a more complex picture of the relationship between sun exposure and melanoma, however. While melanoma incidence is higher in regions near the equator where ultraviolet exposure is most intense, melanoma often occurs in areas of the body not exposed to the sun. In observational studies, intermittent or intense sun exposure was associated with increased risk for melanoma; chronic exposure was associated with lower risk, as was the ability to tan.47

Sunlamp and Tanning Bed Avoidance

Six of 19 case‐control studies found a positive association between use of sun lamps and melanoma risk, but most did not adjust for recreational sun exposure or for the dosage and timing of sunlamp exposure.8 Among 9 studies that examined the duration, frequency, or timing of sunlamp or tanning bed exposure, 4 found a positive association, particularly if the dose of exposure was high and if it caused burning.

Sunscreen Use

Daily sunscreen use on the hands and face reduced the total incidence of squamous cell cancer in a randomized trial of 1,621 residents in Australia (rate ratio [RR], 0.61; 95 percent confidence interval [CI], 0.46 to 0.81).9 Sunscreen had no effect on basal cell cancer. Based on this trial, 140 people would need to use sunscreen daily for 4 ½ years to prevent 1 case of squamous cell cancer. An earlier randomized trial demonstrated that sunscreen use reduced solar keratoses, precursors of squamous cell cancers.10 There are no direct data about the effect of sunscreen on melanoma incidence. An unblinded randomized trial showed children at high risk for skin cancers who used sunscreen developed fewer nevi than those who did not. Several epidemiologic studies have found higher risk for melanoma among users of sunscreens than among non‐users.1113 A recent meta‐analysis of population‐based case‐control studies found no effect of sunscreen use on risk for melanoma.14 The conflicting results may reflect the fact that sunscreen use is more common among fair‐skinned people, who are at higher risk for melanoma, than it is among darker‐skinned people; or, this finding may reflect the fact that sunscreen use could be harmful if it encourages longer stays in the sun without protecting completely against cancer‐causing radiation.

Skin Self‐Examination

The only evidence for the effectiveness of skin self‐examination comes from a single case‐control study.1,15 After adjustment for other risk factors, skin self‐examination was associated with lower incidence of melanoma (odds ratio [OR], 0.66; 95 percent CI, 0.44 to 0.99) and lower mortality from melanoma (OR, 0.37; 95 percent CI, 0.16 to 0.84), although the definition of "self‐examination" was limited. This study did not provide sufficient evidence that skin self‐examination would reduce the incidence of melanoma or improve outcomes of melanoma.

Effectiveness of Counseling

Community and worksite educational interventions have demonstrated effectiveness for increasing the use of skin protection measures, such as wearing hats and long‐sleeve shirts and staying in the shade; however, evidence addressing the effectiveness of clinician counseling to prevent skin cancer is extremely limited. Most studies of counseling have examined intermediate outcomes such as knowledge and attitudes rather than changes in behavior. In a recent survey, 60 percent of pediatricians said that they usually or always counsel patients about skin protection, but advice to use sunscreen is more common than advice about wearing protective clothing or avoiding the midday sun.16

Simple reminders and instructional materials for clinicians can overcome some of the barriers to regular counseling. A randomized trial of a community‐based intervention involving 10 towns in New Hampshire suggests that office‐based counseling by physicians may be an effective component of a multi‐modal program to promote skin protection.17 The proportion of children utilizing some sun protection increased significantly in the intervention towns (from 78 to 87 percent) compared to a decrease in the control communities (from 85 to 80 percent). More parents reported receiving some sun protection information from a clinician in the intervention towns. However, most of the change was due to increased sunscreen use rather than to reduced sun exposure.

Potential Harms of Skin Protection Behaviors

There are limited data regarding potential harms of counseling or of specific skin protection behaviors. A possible result of skin cancer counseling that focuses on the use of sunscreen can lead to a false sense of security, which might lead to more time in the sun. For example, a randomized trial with young adults found that those who used sunscreen with a high sun protection factor (SPF) stayed longer in the sun than those who used sunscreen with a lower SPF.18 There has been some concern that use of sun protection factor (SPF) of 15 results in vitamin D deficiency. However, a randomized trial in people over 40 years of age found that sunscreen use over the summer had no effect on 25‐hydroxyvitamin D3 levels. Concerns related to sun avoidance include reduced physical activity levels among children and negative effects on mental health. However, no studies have evaluated the effects of sun protection behaviors on these outcomes.

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