High-Grade B-Cell Lymphoma of the Sciatic Nerve That Mimicked a Schwannoma: A Case Report

A 41-year-old woman with a history of high-grade B-cell lymphoma status-post chemotherapy was evaluated for a painful left posterior thigh mass and significant weakness with sensory changes. Imaging revealed a benign-appearing mass consistent with schwannoma; however, intraoperative frozen section suggested high-grade B-cell lymphoma. Subsequent restaging studies revealed metastatic disease.

A history of lymphoma warrants careful investigation of a posterior thigh mass, despite imaging findings consistent with nerve sheath tumor. Surgical removal of lymphomas of the nerve often proves futile, so these lesions are usually managed with medical treatment or radiation.