Long-term outcomes of patients with primary or residual vestibular schwannoma treated with LINAC-based stereotactic radiosurgery: a single-centre experience

Abstract

AbstractAim:Vestibular schwannomas (VS) are benign slow-growing tumours treated either with microsurgery or stereotactic radiosurgery (SRS) or both. The aim of this study was to correlate the outcome factors—tumour control and adverse factors—facial nerve function and hearing loss with patient and treatment factors.Materials and methods:A retrospective review of the records of 98 patients with 99 VS treated from June 2007 to June 2014, all patients receiving Linear Accelerator (LINAC)-based SRS.Results:Median follow-up period was 5·6 years (range: 1–12 years). The response to treatment was stable disease in 37 (37·4%), regression in 46 (46·5%), asymptomatic minimal progression in 9 (9·1%) and symptomatic progression in 5 (5%) and unknown in 2 (2%) patients. There was no evidence of SRS induced tissue damage on magnetic resonance scans for any. Hearing preservation rate after SRS was 92%. The patients who developed worsening of facial function were predominantly in the cohort that had prior surgery.Findings:SRS is an effective modality to treat VS lesser than 3 cm in size. Tumour control rate was 95% with a median follow-up period of 5·6 years. The complication rates were 8% each for facial function worsening and worsening of hearing. Prior surgery was a statistically significant factor that affected facial nerve function deterioration.