Dermoscopic findings in a collision tumor composed of a dermatofibroma and a melanocytic nevus mimicking melanoma

Abstract

Collision tumors consist of two different neoplasms occurring concurrently in the same lesion. This association has been described for both benign and malignant neoplasms that may be difficult to identify. Therefore, dermoscopy is a valuable tool to make a correct diagnosis. We report a very unusual collision tumor composed of both a dermatofibroma and a melanocytic nevus mimicking melanoma.