Primary Malignant Peripheral Nerve Sheath Tumor of the Stomach

A Rare Case Report and Review of Literature

Cui, Wenwen MS
Xing, Lihang MS
Fu, Limei MS
Shi, Lifang MS
Li, Xinjun MD

¹Department of Pathology, Binzhou People’s Hospital, Binzhou, China
²Department of Thyroid surgery, Binzhou People’s Hospital, Binzhou, China

Xinjun Li, Department of Pathology, Binzhou People’s Hospital, No. 515, Huanghe 7th Road, Binzhou City, Shandong Province, China. Email: [email protected]

Received January 24, 2022

Received in revised form March 23, 2022

Accepted April 12, 2022

International Journal of Surgical Pathology 31(2):p 221-226, April 2023. | DOI: 10.1177/10668969221098094

Malignant peripheral nerve sheath tumor (MPNST) is a spindle cell sarcoma originating from peripheral nerves or showing differentiation of nerve sheath components. Primary MPNST of the stomach is an extremely rare neoplasm with only a few published reports in the literature. We present the case of a 58-year-old male patient with MPNST in the stomach. The patient was admitted due to upper abdomen discomfort. Gastroscopy revealed a huge ulcer lesion in the stomach, and biopsy revealed a spindle cell malignant neoplasm. No other specific findings were found in the whole-body imaging examination. Subtotal gastrectomy was performed. Histologically, an ulcer-type, push-infiltrating mass composed of dense, woven-like spindle cells with frequent mitosis could be seen. In immunohistochemistry, the tumor cells were negative for expression of H3K27 trimethylation (H3K27me3), keratin (AE1/AE3), epithelial membrane antigen (EMA), CD34, KIT, DOG1 (ANO1), S-100, SOX10, smooth muscle actin, desmin, myogenin, MDM2, CDK4, P16 (CDKN2A) and SS18-SSX (SS18::SSX). Primary MPNST of the stomach was diagnosed based on histological and immunohistochemical results. During the 2.5 years follow-up period after surgery, no recurrence was observed.