RADT-23. STEREOTACTIC RADIOSURGERY FOR CYSTIC VESTIBULAR SCHWANNOMA - A SYSTEMATIC REVIEW

Abstract

Abstract BACKGROUND Cystic vestibular schwannoma, also historically known as cystic acoustic neuroma, is a benign intracranial tumor that can form between the pons and the cerebellum in an area known as the cerebellopontine angle. These brain tumors can be treated with radiotherapy, surgical resection, or radiosurgery. However, there is no consensus on which treatment modality is the most effective with minimal to no complications. METHODS A comprehensive review of clinical articles reporting stereotactic radiosurgery treatment for cystic vestibular schwannoma was performed. PubMed, Web of Science, Cochrane, Scopus, and Embase were independently queried and the PRISMA guidelines were followed throughout the screening process. We identified high-quality studies representing data from 186 patients. We extracted patient demographics, tumor characteristics, type of stereotactic radiosurgery, dosage, tumor control rate, and follow-up time. All the available data points were used to evaluate the effect of stereotactic radiosurgery on tumor control rate for cystic vestibular schwannoma. RESULTS A total of 186 patients underwent stereotactic radiosurgery with Gamma Knife (n = 178) and CyberKnife (n = 8). The average tumor volume was 6.47 cm3 (range 4.82 – 8.4 cm3, SD ± 1.8). The average marginal and maximum doses were 12.8 Gy (12.5 -13 Gy, SD ± 0.25) and 24.9 Gy (23.8 - 26 Gy, SD ± 1.10), respectively. The average follow-up time was 63.5 months (53.5 – 74 months, SD ± 10.2). Following stereotactic radiosurgery treatment for cystic vestibular schwannoma across all studies, almost 92% of patients had tumor control at follow-up, (95%-CI: 91.4 - 91.6). CONCLUSIONS Our systematic review revealed that stereotactic radiosurgery can provide adequate tumor control for cystic vestibular schwannoma. Therefore, stereotactic radiosurgery is an effective treatment choice in patients with cystic vestibular schwannoma.