Orbital malignant melanoma and oculodermal melanocytosis: report of two cases and review of the literature.

Oculodermal melanocytosis is a congenital melanoblastic hamartoma affecting ocular tissues and facial skin. It is seen more commonly in oriental and black patients. Malignant degeneration, once believed to be rare in this syndrome, occurs in 4.6% of all reported cases, and is more frequent in whites. The actual incidence of malignant melanoma in this syndrome is difficult to determine as many uncomplicated cases go unreported. The most common site of malignant melanoma associated with this entity is in the choroid. Four previously described orbital tumors represent the second most frequent area of presentation. A review of the literature in this disease is discussed as well as a new case of orbital malignant melanoma associated with it. A second case of presumed orbital melanoma associated with oculodermal melanocytosis is also discussed.