Familial malignant melanoma.

Two sisters simultaneously developed a superficial spreading malignant melanoma on their legs. Concurrently, a brother was affected with fatal metastatic melanoma. Several explanations for familial malignant melanoma are reviewed, including: 1. Genetically determined predisposition; ,2 Phenotypic and environmental factors; and 3. Infectious etiology (virus?). Relatives of patients who develop malignant melanoma spould be aware that they have a higher risk than the general population of developing this serious type of cancer.