The Surgical Management of Symptomatic Peripheral Nerve Sheath Tumors

OBJECTIVE: To determine the clinical presentation and morbidity of the surgical management of peripheral nerve sheath tumors (PNSTs). METHODS: We performed a retrospective chart review of surgically treated PNSTs at the University of Miami between 1991 and 2008. RESULTS: There were a total of 140 cases, including 87 schwannomas, 34 neurofibromas, and 19 malignant peripheral nerve sheath tumors (MPNSTs). The average age of the total study group was 49.0 years; it was significantly lower for patients with neurofibroma. There was a high correlation between neurofibroma tumors and neurofibromatosis-1. Most patients with benign tumors presented with a painful mass, paresthesias, or numbness without significant weakness. Patients who had previously undergone attempted resections and preoperative biopsy had a significantly increased risk (41%) for developing postoperative neurologic deficits when compared with patients who presented with de novo tumors (15%). Intraoperative monitoring appeared to reduce the risk of postoperative motor deficit, particularly in neurofibromas. Most MPNSTs (>80%) were diagnosed at stage IIB or higher and had a combined mortality rate of 31.6% at 78 months. Tumor size was the best predictor of adverse outcome, as all MPNST mortalities occurred in patients with a tumor size of more than 7 cm. CONCLUSION: PNSTs are a heterogeneous group of lesions. Benign tumors respond well to marginal excision, whereas MPNSTs are aggressive sarcomas that require multimodal management. There was a significantly increased risk of postoperative neurologic deficits in patients who had undergone a previous biopsy, and thus tertiary referral without biopsy is recommended when a PNST is suspected.