Surgical outcome of isolated benign peripheral nerve sheath tumors without neurofibromatosis

Abstract

Benign peripheral nerve sheath tumors (BPNSTs) include schwannomas and neurofibromas. About 10% of soft tissue sarcomas are malignant peripheral nerve sheath tumors (MPNSTs), which are invasive and aggressive tumors. These can happen occasionally or after radiation exposure. Up to 90% of schwannomas are made up of differentiated neoplastic Schwann cells. Malignant transformation of schwannomas is rare. We collected the medical records of all patients (including their family histories), performed comprehensive physical and neurological assessments, and checked for the presence of a Tinel-like sign, as well as screening for neurofibromatosis (NF) signs. Magnetic resonance imaging (MRI), nerve conduction studies, and ultrasound were done for all cases. We have operated on 21 patients with age range 29–52 years. The mean age was 39.4 years. 14 of these patients were females and 7 were males. The presenting symptoms were just swelling at nerve site in 14 patients, spontaneous pain at the nerve sites in 7 patients, and sensory deficit at the nerve distribution sites in 9 patients. The other 12 patients were sensory intact and only 7 patients had motor deficit. Postoperatively all patients had improved motor and sensory deficit and none of intact patients were worsened. Preoperatively we did MRI to show important nearby vascular structure anatomical abnormalities and we ordered nerve studies to all patients that showed abnormalities, which was only in 9 patients. Gross total resection was done in 18 patients and other 3 cases had partial resection to avoid sensory and motor deficits. The pathological analysis revealed 11 schwannomas and 10 neurofibromas. With 1 year follow up there was no recurrence in any patients. Benign pheripheral nerve sheath tumours are safely resected without increased sensory and motor deficits after surgery and with improve clinical outcome with no recurrence on follow up.