Melanoma risk factors and atypical moles.

Despite important advances in the treatment of melanoma, the prognosis for advanced disease remains discouraging. This fact, in combination with a worldwide epidemic of melanoma among persons of white skin type, has focused attention on identifying melanoma in its early, surgically curable stages. Attention has also been directed toward pinpointing which persons are at increased risk for melanoma to reduce risk where possible and to aid early diagnosis. Essentially all epidemiologic studies have identified an increased number of melanocytic nevi as an important risk factor in the development of melanoma, but controversy has arisen concerning the risk associated with certain types of nevi, particularly "dysplastic" nevi. We review melanoma risk factors and examine the relationship between melanocytic nevi and melanoma to clarify for primary care physicians what is "known" (non-controversial) and what is "unknown" (controversial). We propose a working definition of an atypical mole phenotype and outline an approach to managing high-risk patients.