# Squamous Metaplasia in a Schwannoma: A Unique Histologic Finding

## TL;DR

A schwannoma tumor in a 61-year-old woman showed an unusual feature of squamous metaplasia, a finding not previously reported in medical literature.

## Contribution

This paper reports the first documented case of squamous metaplasia within a schwannoma.

## Key findings

- A schwannoma resected from a 61-year-old female contained squamous metaplasia.
- This histologic finding has not been previously reported in the literature.
- The finding may help pathologists recognize atypical presentations of schwannomas.

## Abstract

Schwannomas are benign peripheral nerve sheath tumors that originate from Schwann cells and characteristically display a biphasic appearance of compact hypercellular and myxoid hypocellular areas, named Antoni A and Antoni B areas, respectively. While most schwannomas arise sporadically, they can be associated with familial tumor syndromes such as neurofibromatosis type 2 and Carney complex. Herein, we report a case of a 61-year-old female who had a schwannoma resected from her upper extremity that later revealed a focus of squamous metaplasia associated with the schwannoma, a finding that has not yet been reported in the literature. This unique finding may aid pathologists in the future when confronted with such an atypical presentation in a schwannoma.