Cutaneous malignant melanoma arising in an acquired naevus of Ota

ABSTRACT Naevus of Ota is a dermal melanocytosis most commonly found in black or Asian skin and is usually a benign malformation, but with a low risk of melanoma. We describe a 32‐year‐old Caucasian man with an acquired naevus of Ota with subtle pigmentation, in which a melanocytic papule developed. The lesion, deceptively, had no clinically suspicious features, but investigation revealed an aggressive cutaneous malignant melanoma, extensive orbital ring melanocytosis and metastatic brain and subsequent liver disease.