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

Evidence from several countries suggests that the long-continued increase in melanoma-related mortality is slowing or has ceased. In some countries, decreasing rates are now seen particularly in women. These trends are probably due to successful primary prevention and early diagnosis. However, incidence continues to increase, even in areas of already high incidence such as Australia. Sun exposure has been established as the major cause of cutaneous melanoma in white patients, and no other environmental factors show a consistent association. Links to occupation, diet, and hormonal factors are still not clearly established. The frequency of nevi is likely to be both a good indicator of future melanoma risk and a short-term biologic marker of the effects of sun exposure; valuable new studies on the latitude gradient and natural history of nevi have been published. Primary prevention of skin cancers is now a priority in high-risk countries, and studies in Australia are clarifying the effect of education on sun exposure behavior. Although surveillance of particularly high-risk persons is valuable, the benefits of more widespread targeting or screening of high-risk persons remains unclear. Useful studies on the reliability of diagnostic and screening examinations have been produced, along with preliminary data on the value of diagnostic aids such as epiluminescence microscopy.