Stereotactic radiosurgery for recurrent high-grade gliomas

Abstract

Introduction: High-grade gliomas (WHO Grade III and IV) invariably recur. Standardized management in the recurrent setting is ill defined. Stereotactic radiosurgery (SRS) represents a non-invasive treatment modality. Evidence to date is limited and therefore further evaluation of the role of SRS in recurrent high-grade-gliomas (rHGG) is warranted. Methods: We conducted a retrospective cohort study consisting of 33 patients with rHGGs treated with SRS from January 2020 to June 2024. Baseline demographics, radiosurgical parameters, and outcomes/toxicity data were collected. Descriptive statistics were calculated for all continuous variables. Survival analysis was performed using the Kaplan Meier method. Univariate analysis was performed using Cox proportional hazard model. All statistics were performed in GraphPad Prism (V.10). Results: Thirty-three patients with 44 rHGG lesions underwent Gamma Knife SRS with a median of 5 fractions (range:1–5). Overall local control at 3-,6-, and 12-months was 69.9 %, 45.9 %, and 31.9 % respectively. Distant tumor control at 3-,6-, and 12-months was 71.7 %, 48.2 %, and 42.2 %. Global tumor control was at 3-,6, and 12-months was 69.9 %, 45.9 %, 31.9 % respectively. Median OS from the time of SRS was 7 months (95 % CI: 6.65–17.23). Median PFS from the time of SRS was 5.5 months (95 % CI: 4.79–14.31). MGMT methylated status was associated with improved OS (HR: 0.24 95 % CI: 0.07–0.60, P = 0.01). Conclusions: SRS affords reasonable local control in the short term for patients with recurrent HGG who are otherwise poor surgical candidates. Local failure is more common than distant failure, albeit global control is critical in increasing PFS. MGMT methylated status is associated with increased overall survival.