Long-term quality of life and tumour control following gamma knife radiosurgery for vestibular schwannoma

Abstract

Gamma knife radiosurgery (GKRS) has for the last decades been an established treatment option for patients with small- or medium-sized vestibular schwannomas (VS), although little data is reported on long-term outcome regarding quality of life (QOL) and tumour control in this patient category. The objective of this study was to investigate long-term QOL and tumour control in GKRS-treated VS patients at our institution. Data was reviewed from a consecutive cohort of 128 patients, 62 men and 66 women, diagnosed with VS and treated with GKRS at Karolinska University Hospital between 1997 and 2003. Patients previously treated for VS, patients from abroad, and patients with neurofibromatosis were excluded from the study. Median age at the time of treatment was 66 years (range 23-89), with a median follow-up time of 104 months (range 11-165) and radiological median follow-up of 86 months (range 5-170). Five patients were lost to follow-up. Data on QOL (EQ-5D score) was obtained in 90 % (98/109) of all cases at the end of follow-up, showing low morbidity and a high QOL with median index of 0.91 (max. score 1.0) in these patients. Tumour control was achieved in 92 % (118/128) of patients after a single GKRS treatment. Ten patients had loss of tumour control, either radiologically seen as growth progression, or due to the need for salvage treatment. Neither pre-treatment growth of the vestibular schwannoma, or a large tumour size (Koos grade 3 & 4) was correlated with a higher degree of treatment failure (p = 0.695 and p = 0.647, respectively). There was no difference in tumour control in young (<60 y/o) vs. elderly (≥60 y/o) patients (p = 0.167). We report a high QOL and low morbidity at long-term follow-up after GKRS treatment in VS patients. Furthermore, a high tumour control rate was achieved independent of tumour size, patient age or pre-treatment evidence of tumour growth.