A case of plexiform palisaded encapsulated neuroma of the penis

Palisaded encapsulated neuroma (PEN) is a benign cutaneous neural tumor. It usually presents in adults as a solitary asymptomatic skin-colored papule that is almost always on the face. We report here on an uncommon case of plexiform PEN that developed on the penis of a 43-year-old man. It was 6 mm-sized skin colored papule. Histologically, there is an encapsulated nodule with a plexiform growth pattern in the dermis and a palisading arrangement of nuclei. On immunohistochemical staining, the tumor cells of the nodule were positive for S-100 and neurofilament.