Malignant melanoma in World War II veterans.

In a consecutive series of 1,067 patients entered into the data base of the Melanoma Cooperative Group at New York University School of Medicine between 1972 and 1980, 120 men were of draft age (18-31 years) during World War II (1941-1945). Questionnaires were sent to these 120 individuals; 89 responded. Simultaneously, a control (nonmelanoma) population of 65 men of similar age was queried. Each subject in both groups was asked whether he had served in the armed forces during World War II and, if so, what were his theaters of operation. Based on the response, 83% (74 of 89) of the melanoma group compared with 76% (49 of 65) of the control group had served in the armed forces during World War II; however, a significantly (p = 0.0002) greater percent of the melanoma patients (34%) served in the tropics than did the control subjects (6%). Further, overrepresented in the melanoma group that served in the tropics (compared with the melanoma group who served in the armed forces in nontropical theaters) were malignant melanomas that had their origin in nevocytic nevi. The findings suggest that Caucasian individuals heavily exposed to sunlight in the tropics for several years during early life may be at higher risk to the subsequent development of cutaneous malignant melanoma. In some individuals this may be a two-step phenomenon, in which the first step is the solar induction of nevocytic nevi and the second is malignant transformation within them.