Abstract
BACKGROUND: Following large resection, proposing a watch-and-wait strategy in selected grade 3 glioma, isocitrate dehydrogenase (IDH)-mutant patients is an emerging practice. We compared the watch-and-wait approach to the standard postoperative adjuvant oncological treatment for grade 3 gliomas, IDH-mutant. METHODS: Observational, retrospective, single-institution cohort (2011-2023) of 106 consecutive adult patients harboring supratentorial grade 3 gliomas, IDH-mutant treated by maximal awake resection and who received a watch-and-wait approach (surgery group) or an adjuvant oncological treatment (oncological group) postoperatively. Case-matched analysis (1:1) criteria between the surgery group and oncological group: extent of resection, tumor volume, Karnofsky Performance Status (KPS) score, tumor location and size, and age. RESULTS: Patients of the surgery group (n = 26) had significantly better KPS scores, less preoperative neurological and/or neurocognitive deficits, less hyperperfusion, less corpus callosum infiltration, smaller tumor volume, higher rate of total resection, and smaller residual tumor than patients of the oncological group (n = 80). The 5-year progression-free survival (66.2 vs. 77.9 months, P = .713) and the 5-year overall survival (88.9 vs. 83.9 months, P = .291) did not differ between surgery and oncological groups. In the whole series, a preoperative KPS score >70, a total resection, and the oligodendroglioma subtype were independent predictors of longer progression-free survival and overall survival. After case matching, no difference in survival was observed between watch-and-wait and oncological treatment both in astrocytomas (n = 14 per group) and oligodendrogliomas (n = 12 per group). CONCLUSIONS: Watch-and-wait following radical resection appears to be feasible in highly selected grade 3 gliomas, IDH-mutant patients without impairing survival both in astrocytoma and in oligodendroglioma subgroups.