Cutaneous malignant melanoma in survivors of heritable retinoblastoma.

Six survivors of bilateral retinoblastoma developed cutaneous malignant melanoma 20 to 51 years (average, 31 years) after initial therapy for the ocular tumor. Five patients received radiation therapy to the orbital area. In two patients the cutaneous malignant melanoma developed in the field of irradiation. Two patients developed multiple cutaneous melanomas and are thought to have the dysplastic nevus syndrome. At this writing two patients are alive and well after wide resection of their skin tumors. A review of the literature suggests that cutaneous malignant melanoma accounts for about 7% of second malignant neoplasms in survivors of heritable retinoblastoma.