Rapidly progressive spinal epithelioid malignant peripheral nerve sheath tumor following subtotal resection surgery:...

Due to the rarity of spinal epithelioid malignant peripheral nerve sheath tumor (EMPNST), the diagnosis, treatment and prognosis of this condition are limited.

A 67-year-old male patient presented to our hospital with pain in his right shoulder. Imaging studies identified a T2 spinal tumor. The patient underwent T2 vertebral tumor subtotal resection, spinal canal decompression, and C7-T4 percutaneous pedicle screw fixation because he had shown signs of spinal cord compression. Postoperatively, H&E staining revealed numerous malignant tumor cells with epithelioid characteristics. Immunohistochemical analysis of the tumor cells demonstrated weak positivity for cytokeratin, a TP53 mutation, and retained expression of H3K27me3 and SMARCB1/INI1. The cells were negative for S-100, Sox-10, HMB-45, ALK-1, CD23, CD30, CD34, Desmin, epithelial membrane antigen, smooth muscle actin, and Stat6. Based on these findings, a diagnosis of EMPNST was established. On the 10th day following the initial surgery, swelling was observed at the surgical incision site. Subsequent imaging studies confirmed tumor progression. A comprehensive strategy that integrated surgical resection with intraoperative radiotherapy (IORT) and postoperative radiotherapy were implemented; however, these interventions did not yield favorable results. Unfortunately, the patient passed away shortly after treatment.

We present a rare case of spinal EMPNST that was negative for both S-100 protein and SOX10, while retaining expression of SMARCB1/INI1. Notably, the patient did not benefit from IORT and postoperative radiotherapy because these treatments failed to stop the fast tumor growth or enhance neurological results in this particular situation.