Multiple Ancient Schwannomas of the Ulnar Nerve at Distant Sites

Schwannoma, a benign peripheral nerve tumor, rarely undergoes chronic degenerative changes and progresses to ancient schwannoma. Herein, we report the first case of ulnar nerve-derived multiple ancient schwannomas, which uncommonly developed in the extremities and major nerves. A 76-year-old female patient presented with tingling sensations in her left ring and small fingers. She had a gradually enlarging mass that developed 40 years ago in the proximal upper arm and a new mass growing on the wrist for the past few years. Based on physical examination, ultrasonography, and magnetic resonance imaging, ancient schwannomas of the ulnar nerve were suspected. The older and larger mass of the upper arm was more entangled with nerve fascicles, having necrotic changes. Through meticulous dissection of the nerve fascicles, both masses were successfully enucleated, and pathological examination confirmed ancient schwannoma. As ancient schwannomas grow, they become more entangled with the nerves; thus, early surgical removal is recommended.