title: Whether gamma knife radiosurgery is really necessary for treatment of patients with vestibular schwannomas.
abstract: The present study was directed at establishing the role of Gamma Knife radiosurgery (GKS) in the management of vestibular schwannomas (VSs), particularly those that are large. We analyzed a consecutive series of 222 tumors operated on by a single neurosurgeon (T. Hori) at Tottori University (1981-1998) and Tokyo Women's Medical University (1998-2011). The surgical strategy for sporadic unilateral VSs was typically total or nearly total tumor removal with facial nerve preservation, whereas in some cases of neurofibromatosis type 2 intentional subtotal resection was performed. In all, 15 patients (8.6 %) in the series underwent GKS before (4 cases), after (9 cases), or before and after (2 cases) tumor removal. Overall, 211 patients (95 %) were cured by microsurgery alone. Of note, six patients underwent primary radiosurgery but were operated later on for regrowth of the neoplasm, and in four of them near-total resection led to good long-term tumor control. GKS was required in only 5 % of cases for management of residual VS or, more frequently, its regrowth. Radiosurgery resulted in volume reduction in one-third of these tumors. In other cases it stabilized the lesion, preventing further progression. Thus, GKS is considered a reasonable management option for residual or regrowing small VSs to obtain maximum tumor growth control after initially attempting complete surgical removal.
authors: Department of Neurosurgery, Neurological Institute, Tokyo Women's Medical University, Tokyo, Japan. thori@moriyamaikai.or.jp
authors: Tomokatsu
authors: T
authors: Hori
authors: Takashi
authors: T
authors: Maruyama
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D009464:Neuroma, Acoustic / Q000601:surgery*; D016634:Radiosurgery / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome