Two-staged resections for huge fronto-temporo-insular glioma: Single-center experience with 8 patients

Purpose: Insular glioma often invades into the frontal and/or temporal lobes, leading to huge expansion of tumor volume. Surgical removal of huge fronto-temporo-insular glioma (FTIG) remains challenging, and we have removed huge FTIGs using two-staged resections. This report aimed to review our experiences and discuss the adaptation, interval, risks, and outcomes of two-staged resections for huge FTIG. Methods: Eight patients with huge FTIG comprising 7 isocitrate dehydrogenase 1 (IDH) -mutant gliomas and one IDH-wild glioblastoma, underwent two-staged resections. Tumors in the cerebral lobes were resected in the first operation. After a mean interval of 44.5 days, insular glioma and remaining tumor in the cerebral lobes were resected under awake and sedated conditions in the second operation. Results: Mean tumor volume was 126.7 ± 24.5 cm 3 and mean extent of resection (EOR) after the second operation was 84.8 ± 10.8%. However, EOR was 78.7% in patients with FTIG invading into the basal ganglia or sitting in the left cerebrum. No patients showed adverse events of grade 3 or 4. During the interval between operations, hyperintensity volume on fluid-attenuated inversion recovery imaging remained stable or was slightly reduced in all patients. Median progression-free survival was 1082 days. Conclusion: These findings suggested that two-staged resections represented feasible surgical option, in particularly for IDH-mutant FTIG. However, further studies including more subjects and comparisons to single-staged resection are needed to verify the benefits of two-staged resections for huge FTIG.