Long-Term Results of CyberKnife Radiosurgery for Vestibular Schwannoma / 대한평형의학회지

ABSTRACT

OBJECTIVE: Since the 2000s, CyberKnife radiosurgery (CKRS) is either a primary or an adjunct management approach used to treat patients with vestibular schwannoma (VS). The goals of CKRS are prevention of tumor growth, preservation of cranial nerve function and prevention of new neurologic deficiencies. The aim of this study was to assess the efficacy and safety of CKRS, in terms of tumor control, hearing preservation, and complications. METHODS: Forty patients with VS underwent CKRS as a treatment modality for from January 2010 to February 2016. The long term results of 32 patients were evaluated who received CKRS as primary treatment. 8 patients presented with previously performed surgical resection. Information related to clinical history, Brain MRI and outcomes of patients with VS collected retrospectively by reviewing patient's chart and telephone survey. RESULTS: The mean tumor volume was 3.3 cm³ and the mean follow-up was 41 months. The most recent follow-up showed that tumor size decreased in 17 patients (42.5%), displayed no change in 19 patients (47.5%), and increased in 4 patients (10%). Progression-free survival rates after CKRS at 1, 3, and 5 years were 95%, 90%, and 90%. After CKRS, 13 patients experienced hearing degradation. The overall rate of preservation of serviceable hearing at the long-term follow-up was 60%. Vertigo, ataxia, and headache were improved after CKRS compared with pretreated status. But, facial weakness, trigeminal nerve neuropathy, and tinnitus were worsen. CONCLUSION: CKRS provide an excellent tumor control rate and a comparable hearing preservation rate in VS patients. Also CKRS is associated with low rate of cranial neuropathy, other complications.