Solitary circumscribed neuroma of the upper lip: A case report

Abstract

A solitary circumscribed neuroma is a benign peripheral nerve tumor with a predilection for the skin of the head and neck. Herein, we present a 73-year-old Japanese male with a solitary circumscribed neuroma of the upper lip. Histologically, the tumor comprised densely proliferating Schwann cells and axons that formed fascicles. A thin perineural-derived fibrous capsule surrounded the tumor. Immunohistochemically, the tumor cells were positive for S-100, and neurofilaments indicated the presence of nerve fibers. Fibrous capsules were identified by epithelial membrane antigen staining.