Efficacy of Gamma Knife Radiosurgery for Recurrent Gliomas

Objective: To investigate the efficacy and safety of gamma knife radiosurgery (GKRS) for recurrent gliomas. Methods: : We retrospectively analyzed 88 patients who underwent GKRS in our department from 2009 to 2020, including 56 cases of high-grade glioma (HGG) and 32 cases of low-grade glioma (LGG). The median target volume was 17.8 cm 3 (1.6–124.1), the median maximum dose was 25 Gy (13.5–42 Gy), and the median marginal dose was 13.0 Gy (7.5–24.5 Gy). The Kaplan–Meier method was used to calculate the overall survival (OS) and progression free survival (PFS), and log rank test was used to analyze the multivariate prognosis of the Cox proportional-hazards model. Adverse reactions were evaluated according to the Common Terminology Criteria for Adverse Events version 4.03 (CTCAE). Results: : The median follow-up time was 79.5 months. The median OS and PFS were 12.5 months and 5.0 months for all patients. The median OS and PFS were 10.0 months and 4.5 months for HGG, respectively. The median OS and PFS were 27.0 months and 12.0 months for LGG, respectively. Multivariate analysis showed that Karnofsky performance status (KPS), pathological grade and the times of GKRS significantly affected OS and PFS. Stratified analysis showed that recurrence time interval (15 months) significantly affected OS and PFS for LGG. KPS significantly affected OS and PFS for HGG, and tumor volume (25 cm 3 ) significantly affected PFS for HGG. No serious adverse events were noted post-GKRS. Conclusions: : Gamma knife radiosurgery as a salvage treatment for recurrent gliomas was safe and effective with tolerable adverse reactions.