Insular Gliomas. Experience in a Latin American Center and Assessment of Variables Related to Surgical Management and Prognosis

Abstract

OBJECTIVE: To describe our experience in the resectionof gliomas involving the insula and analyze the variablesimplicated in the management and prognosis of thesetumors.METHODS: This retrospective, single-center, analyticstudy included a cohort of 83 patients who underwentsurgery for insular gliomas by the same surgeon in a thirdlevel Argentine center, in the period between 2010 and2023. We analyzed the population’s demographic, clinical,and radiologic features and surgical variables associatedwith postoperative results and prognosis using multivariateregression analysis.RESULTS: A total of 53 patients (54% men) wereincluded, with a mean follow-up of 40.7 months. The meanage at surgery was 41 years (range, 21e73) and 66.1%corresponded to low-grade gliomas (LGGs). Seizures werethe initial symptom in most cases. There was evidence oftumor extension over the insula to the temporal or/andfrontal lobe in 64.2% of patients. An extent of resection>90% was achieved in 62.3% of cases (27% of gross totalresection), with an average resected volume of 89.4%.Awake craniotomy was indicated in 47% of patients andintraoperative magnetic resonance imaging was performedin 24%. Recurrence was observed in 44% of patients, with amean progression-free survival of 31 months (42 months inLGG and 10 months in high-grade glioma [HGG]). Nine patients underwent reoperation. By the time of 2 years,survival was 100% for LGG and 46% for HGG, whereas4-year overall survival was 92% for patients with LGG and15.4% for those with HGG. CONCLUSIONS: Surgery for insular gliomas is a complex task that needs to be managed with adequatepreoperative and intraoperative assessment to achievemaximum safe resection with low morbidity for betterfunctional and oncologic outcomes. Adequate anatomicunderstanding, radiologic analysis, awake craniotomy, andcortical and subcortical mapping are paramount to pursuethis aim.