title: Neurological outcomes and surgical complications in 221 spinal nerve sheath tumors.
abstract: OBJECTIVE Among all primary spinal neoplasms, approximately two-thirds are intradural extramedullary lesions; nerve sheath tumors, mainly neurofibromas and schwannomas, comprise approximately half of them. Given the rarity of these lesions, reports of surgical complications are limited. The aim of this study was to identify the rates of new or worsening neurological deficits and surgical complications associated with the resection of spinal nerve sheath tumors and the potential factors related to these outcomes. METHODS Patients were identified through a search of an institutional neuropathology database and a separate review of current procedural terminology (CPT) codes. Age, sex, clinical presentation, presence of neurofibromatosis (NF), tumor type, tumor location, extent of resection characterized as gross total or subtotal, use of intraoperative neuromonitoring, surgical complications, presence of neurological deficit, and clinical follow-up were recorded. RESULTS Two hundred twenty-one tumors in 199 patients with a mean age of 45 years were identified. Fifty-three tumors were neurofibromas; 163, schwannomas; and 5, malignant peripheral nerve sheath tumors (MPNSTs). There were 70 complications in 221 cases, a rate of 32%, which included 34 new or worsening sensory symptoms (15%), 12 new or worsening motor deficits (5%), 10 CSF leaks or pseudomeningoceles (4%), 11 wound infections (5%), 5 cases of spinal deformity (2%), and 6 others (2 spinal epidural hematomas, 1 nonoperative cranial subdural hematoma, 1 deep venous thrombosis, 1 case of urinary retention, and 1 recurrent laryngeal nerve injury). Complications were more common in cervical (36%) and lumbosacral (38%) tumors than in thoracic (18%) lesions (p = 0.021). Intradural and dumbbell lesions were associated with higher rates of CSF leakage, pseudomeningocele, and wound infection. Complications were present in 18 neurofibromas (34%), 50 schwannomas (31%), and 2 MPNSTs (40%); the differences in frequency were not significant (p = 0.834). Higher complication rates were observed in patients with NF than in patients without (38% vs 30%, p = 0.189), although rates were higher in NF Type 2 than in Type 1 (64% vs 31%). There was no difference in the use of intraoperative neuromonitoring when comparing cases with surgical complications and those without (67% vs 69%, p = 0.797). However, the use of neuromonitoring was associated with a significantly higher rate of gross-total resection (79% vs 66%, p = 0.022). CONCLUSIONS Resection is a safe and effective treatment for spinal nerve sheath tumors. Approximately 30% of patients developed a postoperative complication, most commonly new or worsening sensory deficits. This rate probably represents an inevitable complication of nerve sheath tumor surgery given the intimacy of these lesions with functional neural elements.
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Safaee
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Russ
authors.initials: R
authors.lastname: Lyon
authors.affiliation: Department of Neurological Surgery, Indiana University, Indianapolis, Indiana.
authors.forename: Nicholas M
authors.initials: NM
authors.lastname: Barbaro
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Dean
authors.initials: D
authors.lastname: Chou
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Praveen V
authors.initials: PV
authors.lastname: Mummaneni
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Philip R
authors.initials: PR
authors.lastname: Weinstein
authors.affiliation: Radiology, and.
authors.forename: Cynthia T
authors.initials: CT
authors.lastname: Chin
authors.affiliation: Department of Pathology, Neuropathology Unit, University of California, San Francisco, California; and.
authors.forename: Tarik
authors.initials: T
authors.lastname: Tihan
authors.affiliation: Departments of 1 Neurological Surgery.|Orthopedic Surgery; and.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Ames
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008161:Lumbosacral Region; D008297:Male; D008875:Middle Aged; D018317:Nerve Sheath Neoplasms / Q000453:epidemiology / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D012189:Retrospective Studies; D013120:Spinal Cord Neoplasms / Q000453:epidemiology / Q000601:surgery*; D013904:Thoracic Vertebrae; D016896:Treatment Outcome; D055815:Young Adult
keywords: DVT = deep venous thrombosis; EMG = electromyography; GTR = gross-total resection; MEP = motor evoked potential; MPNST = malignant PNST; NF1, NF2 = neurofibromatosis Type 1, Type 2; PNST = peripheral nerve sheath tumor; SSEP = somatosensory evoked potential; STR = subtotal resection; nerve sheath tumor; neurofibroma; oncology; schwannoma; spine