Iris melanoma arising in iris nevus in oculo(dermal) melanocytosis.

A 50-year-old white man with oculo(dermal) melanocytosis and longstanding iris nevus was found to have growth of the iris mass. Excision and histopathologic examination revealed a mixed cell type malignant melanoma. Benign nevus cells were present at the periphery of the tumor surrounding the entire melanoma. White patients with oculo(dermal) melanocytosis have a predisposition to uveal melanoma, which is usually choroidal in origin. Literature review showed only three confirmed cases of iris melanoma in this setting. Two additional cases initially published as spindle A melanoma have been reclassified as iris nevi based on the modified Callender classification of uveal melanomas. It is recommended that patients with oculo(dermal) melanocytosis be followed for the occurrence of uveal melanoma.