Malignant melanoma occurring within a previously irradiated area.

The commonest radiation-induced neoplasms are sarcomas. Ionizing radiation is not usually associated with the development of malignant melanoma. We report two patients with malignant melanoma occurring within a previously irradiated area. There is evidence to support radiation in the pathogenesis of melanoma but the family histories, especially in one patient, suggest that genetic mutations may also have played a role, particularly in relation to the short latent period.