Vestibular schwannoma international study of active surveillance versus stereotactic radiosurgery: the VISAS study

Abstract

Purpose: The present study assesses the safety and efficacy fi cacy of stereotactic radiosurgery (SRS) versus observation for Koos grade 1 and 2 vestibular schwannoma (VS), benign tumors affecting hearing and neurological function. Methods and Materials: This multicenter study analyzed data from Koos grade 1 and 2 VS patients managed with SRS (SRS group) or observation (observation group). Propensity score matching balanced patient demographics, tumor volume, and audiometry. Outcomes measured were tumor control, serviceable hearing preservation, and neurological outcomes. Results: In 125 matched patients in each group with a 36-month median follow-up (P = .49), SRS yielded superior 5- and 10- year tumor control rates (99% CI, 97.1%-100%, and 91.9% CI, 79.4%-100%) versus observation (45.8% CI, 36.8%-57.2%, and 22% CI, 13.2%-36.7%; P < .001). Serviceable hearing preservation rates at 5 and 9 years were comparable (SRS 60.4% CI, 49.9%-73%, vs observation 51.4% CI, 41.3%-63.9%, and SRS 27% CI, 14.5%-50.5%, vs observation 30% CI, 17.2%-52.2%; P = .53). SRS were associated with lower odds of tinnitus (OR = 0.39, P = .01), vestibular dysfunction (OR = 0.11, P = .004), and any cranial nerve palsy (OR = 0.36, P = .003), with no change in cranial nerves 5 or 7 (P> > .05). Composite endpoints of study tumor progression and/or any of the previous outcomes showed significant fi cant lower odds associated with SRS compared with observation alone (P < .001). Conclusions: SRS management in matched cohorts of Koos grade 1 and 2 VS patients demonstrated superior tumor control, comparable hearing preservation rates, and significantly fi cantly lower odds of experiencing neurological deficits. fi cits. These fi ndings delineate the safety and efficacy fi cacy of SRS in the management of this patient population.