Safety and Efficacy of Hypofractionated Stereotactic Radiosurgery for High-Grade Gliomas at First Recurrence: A Single-Center Experience
Abstract Background: The optimal treatment for recurrent high-grade gliomas (rHGG) remains uncertain. This research aimed to investigate the efficacy and safety of CyberKnife radiosurgery as a salvage treatment for high-grade gliomas at first recurrence that within the radiation field.Methods: Between January 2016 and October 2019, rHGG patients treated with CyberKnife radiosurgery were retrospectively analyzed. The primary endpoint was OS, and secondary endpoints included progression-free survival (PFS) and toxicity. Toxicity was assessed using CTCAE 5.0. The prognostic value of key clinical features (age, performance status, planning target volume, dose, use of bevacizumab) were evaluated.Results: A total of 70 patients were included in the study. Forty patients were male and 30 were female. Forty-nine had an initial diagnosis Glioblastoma (GBM), and rest (21) were WHO Grade 3 Gliomas. The median planning target volume (PTV) was 16.68 cm3 (0.81–121.96 cm3). The median prescribed dose was 24 Gy (12-30 Gy) in 4 fractions (2-6 fractions). Median baseline Karnofsky Performance Status (KPS) is 70 (40-90). With a median follow-up of 12.1 months, the median overall survival after salvage treatment was 17.6 months (19.5 and 14.6 months for grade 3 and 4 gliomas; p = 0.039). No grade 3 or higher toxicities was recorded. Multivariate analysis showed concurrent bevacizumab with radiosurgery and KPS>70 were favorable prognostic factors for grade 4 patients.Conclusions: Salvage CyberKnife radiosurgery showed a favorable outcome and acceptable toxicity for rHGG. A prospective phase II study (NCT04197492) is ongoing to further investigate the value of HSRS in rHGG.