A relation between childhood sun exposure and dysplastic nevus syndrome among patients with nonfamilial melanoma.

We studied 117 patients with nonfamilial melanoma to determine whether melanoma patients with dysplastic nevus syndrome might be distinguished, on the basis of solar exposure, from melanoma patients without dysplastic nevus syndrome. Study participants were interviewed and received a skin examination, which included a total count of nevi, a standardized assessment of clinically atypical nevi, and the excision of each patient's clinically most atypical nevus. Based on the histologic review of the clinically most atypical nevus, each patient was classified as to whether dysplastic nevus syndrome was present or absent. Childhood sunburn with blistering and childhood recreational sun exposure were found to be associated with dysplastic nevus syndrome. The results suggest that childhood sun exposure increases risk of melanoma by initiating the melanoma precursor syndrome.