Etiology, epidemiology, risk factors, and public health issues of melanoma.

Evidence for an increase in the incidence of melanoma and nonmelanoma skin cancers continues to accumulate. Survival after early melanoma is greater than 90%. Survival decreases as tumor thickness increases in a relationship that appears to be more smooth than stepwise. Further evidence that early intermittent sun exposure is a major determinant of risk for melanoma was derived from a case control study in a low-risk population and in a study on migrants to Australia. There is also additional evidence that clinically atypical nevi (dysplastic nevi) are strong predictors of melanoma risk. For public health efforts to be effective in reducing the mortality and morbidity from melanoma and nonmelanoma skin cancers, it is essential to understand the responses of the public and the professional to skin cancer detection efforts and educational programs. Results from several such programs are reviewed. An understanding of the genetics of melanoma continues to grow yet remains complex.