IMG-111. Impact of IDH mutation status and tumor location on language-related brain activation in glioma patients: an fMRI study

Abstract INTRODUCTION Isocitrate dehydrogenase (IDH) mutation status significantly alters prognosis and glioma biology. However, its influence on functional brain organization, particularly in language processing, remains less understood. Investigating the relationship between IDH status and language-related brain activation can provide insights into neuroplasticity and functional reorganization in glioma patients, guiding both clinical decision-making and surgical planning. METHODS Task fMRI was used to measure response of the brain to language tasks (receptive (true-false, sentence completion) and expressive (antonyms, silent letter word generation)) in patients with IDH wildtype (WT) and IDH-mutant gliomas. Phonemic fluency and accuracy were acquired for all patients during the True/False task. RESULTS Images from n = 84 IDH-mutant (48 males, 36 females; mean age = 41.3 ± 12.8 years), and n = 72 IDH-WT (48 males, 24 females; mean age = 58.6 ± 15.6 years) were analyzed. Activation in Broca area for the Expressive language task in IDH-WT was greater than IDH Mutant, with left frontal glioma (p <.05). Activation in Wernicke area and Broca area for the receptive task was greater for IDH-mutant than IDH-WT, with left temporal glioma (p <.05). CONCLUSIONS IDH-WT gliomas in the left frontal lobe are associated with greater activation in Broca’s area during expressive language tasks, suggesting increased cognitive effort or compensation in more aggressive glioma types. Conversely, IDH-mutant gliomas in the left temporal lobe show higher activation in both Broca’s and Wernicke’s areas during receptive language tasks, indicating altered but active engagement of the language network. These findings suggest that the brain adapts differently to IDH status and tumor location, which has important implications for cognitive outcome prediction in patients with glioma.