Insular Gliomas. Experience in a Latin-American center and assessment of variables related to surgical management and prognosis.

OBJECTIVE To describe our experience in the resection of gliomas involving the insula and analyze the variables implicated in the management and prognosis of these tumors. MATERIALS AND METHODS This retrospective, single-center, analytical study included a cohort of 83 patients who underwent surgery for insular gliomas by the same surgeon in a third-level Argentine center, in the period between 2010-2023. We analyzed the population's demographic, clinical, and radiological features and surgical variables associated with postoperative results and prognosis using multivariate regression analysis. RESULTS A total of 53 patients (54% males) were included with a mean follow-up of 40.7 months. Mean age at surgery was 41 years (range 21-73) and 66.1% corresponded to low-grade gliomas. Seizures were the initial symptom in the majority of cases. There was evidence of tumor extension over the insula to temporal or/and frontal lobe in 64.2% of patients. An EOR over 90% was achieved in 62.3% of cases (27% of GTR) with an average resected volume of 89.4%. Awake craniotomy was indicated in 47% of patients and iMRI was performed in 24%. Recurrence was observed in 44% of patients with a mean Progression-Free survival of 31 months (42 months in LGG and 10 months in HGG). A total of 9 patients were re-operated. By the time of 2 years, survival rates were 100% for LGG and 46% for HGG, while 4-year overall survival rates were 92% for patients with LGG and 15.4% for those with HGG. CONCLUSION Surgery for insular gliomas is a complex task that needs to be managed with adequate preoperative and intraoperative assessment in order to achieve maximum safe resection with low morbidity for better functional and oncological outcomes. Adequate anatomical understanding, radiological analysis, awake craniotomy, cortical and subcortical mapping are paramount to pursue this aim.