PATH-31. Prognostic impact of isocitrate dehydrogenase mutation on overall survival in gliomas: a retrospective analysis from Panama

Abstract

Abstract INTRODUCTION Despite the recognized prognostic value of isocitrate dehydrogenase (IDH) mutations in gliomas, real-world survival data from low- and middle-income countries (LMICs), particularly in Latin America, are scarce. This study aimed to evaluate the prognostic impact of IDH mutation status on overall survival (OS) in a national cohort from Panama. MATERIALS AND METHODS We retrospectively analyzed 196 glioma patients diagnosed between 2018 and 2023 at the National Oncology Institute of Panama. Tumor histology and grade were classified according to the 2021 WHO Classification. IDH mutation status was assessed via immunohistochemistry. Patients with ependymoma or incomplete clinical records were excluded. Epidemiological variables, treatment modalities, tumoral and molecular characteristics were collected. Kaplan–Meier survival curves, log-rank tests, and Cox regression models were applied. Analyses were performed using SPSS 30.0. The study protocol was approved by the Bioethics Committee of The Panama Clinic (EC-CBITPC-063). RESULTS Among 196 patients, 59 (30%) were IDH-mutant and 137 (70%) IDH wild-type. Median OS was not reached for the IDH-mutant group but was 11.4 months (95% CI: 8.3–14.5) in the IDH wild-type group (p < 0.001). Median follow-up time was 34.23 months (95% CI: 25.9–42.5). A total of 123 patients (62.8%) died during follow-up. On multivariable analysis, age ≥ 65 years (HR 1.76; p = 0.008), biopsy-only procedure (HR 2.04; p = 0.004), and Karnofsky Index < 70% (HR 2.02; p = 0.010) predicted worse OS. IDH mutation (HR 0.25; p < 0.001) and frontal-lobe location (HR 0.61; p = 0.039) were associated with improved survival. CONCLUSION In this cohort, IDH mutation emerged as a strong independent predictor of OS. These findings support the routine implementation of IDH testing and expanded access to molecular diagnostics in glioma care across LMICs. Prospective studies are warranted to validate these results.