Cutaneous malignant melanoma after Hodgkin's disease.

Eight cutaneous malignant melanomas occurred in 6 of 1405 patients with Hodgkin's disease, although the expected incidence rate was 0.77 (relative risk, 8; 95% confidence interval, 3 to 17). One melanoma was a thin, level II lesion less than 0.76 mm thick; the rest were mostly bulky, deeply invasive lesions despite close clinical surveillance. The melanomas spread aggressively; 3 of 6 patients died within 1 to 3 years. Two of the six patients developed a second primary malignant melanoma 1 year after the first. Two of six patients had biopsy-proven dysplastic nevus syndrome, a known precursor to cutaneous malignant melanoma, and an additional 3 patients had clinical evidence of dysplastic nevus syndrome. Histologically, the malignant melanomas showed a sparse inflammatory infiltrate, an abnormal host response seen previously in cutaneous melanomas developing in immunosuppressed patients. Dysplastic nevi may identify patients at highest risk who require modified medical management.