43 Determinants of Survival Following Re-resection for Recurrent High-Grade Glioma: A Single-Centre Retrospective Cohort Study

Introduction Evidence is limited to define which patients derive meaningful survival benefit from re-resection of recurrent high-grade glioma (HGG). This study aimed to identify clinical determinants of overall survival (OS) in a cohort of patients undergoing surgical resection for HGG, with secondary analysis of the re-resection subgroup. Methods A retrospective single-centre analysis was performed on consecutive patients undergoing HGG resection from 2020-2021. OS was calculated from the date of first resection to death or censorship. A multivariate Cox proportional hazards (PH) model was implemented to identify independent predictors of OS. A secondary Cox PH model was performed in the re-resection subgroup, with OS calculated from the date of second resection. Results Of 70 patients identified, 18 (25.7%) underwent re-resection for recurrent disease. In the whole-cohort multivariate model, re-resection was associated with a 69% reduction in hazard of death (HR 0.306, p = 0.001). Median OS from the second resection was 12.9 months (IDH wildtype: 12.2 months; mutant: 35.1). No independent predictors of post-re-resection survival reached statistical significance. However, clinically relevant trends were observed: adjuvant therapy (HR 0.306, p = 0.169), and absence of surgical complications following re-resection trended towards improved survival (HR 0.648, p = 0.460). Greater extent of second resection is modestly protective (HR 0.991 per %, p = 0.596). Conversely, IDH wildtype (HR 1.963, p = 0.622) and higher ASA grade at re-resection (HR 1.256, p = 0.663) trended towards poorer survival. Conclusions Re-resection was the strongest independent predictor of improved survival in this cohort of high-grade glioma patients. Due to limited sample size in the current re-resection subgroup, no independent factor predicted post-re-resection survival. Prospective studies with larger cohorts are warranted to confirm meaningful selection criteria.