CNSC-08. TUMOUR-INFILTRATED CORTEX PARTICIPATES IN LARGE-SCALE COGNITIVE CIRCUITS

• DOI: 10.1093/neuonc/noac209.089
• Publication Date: 2022-11-14T07:49:28Z
• Authors: Ayan Mandal; Moataz Assem; Rafael Romero-Garcia; Pedro Coelho; Alexa McDonald; Emma Woodberry; Robert Morris; Stephen Price; John Duncan; Thomas Santarius; John Suckling; Michael Hart; Yaara Erez

Abstract In neurosurgery, tumour-infiltrated cortex is generally assumed to be non-functional. While prior studies have suggested integration of tumour-infiltrated tissue in relatively local circuits responsible for language and motor function, it is unknown whether such tissue can participate in distributed networks important for higher-order cognitive abilities like executive function. We tested the hypothesis that diffuse low-grade gliomas integrate into large-scale cognitive circuits using intracranial electrocorticography and resting-state functional magnetic resonance imaging of four patients. To identify brain areas recruited for executive function, electrocorticography recordings were acquired from tumour-infiltrated tissue under three conditions: i) baseline (rest), ii) simple counting (1-20; “easy”), and iii) switch counting (1-a-2-b-3-c etc.; “hard”). In each patient, we observed significant task-based high gamma power modulations in tumour-infiltrated cortex in response to increasing cognitive effort (p < 0.05), implying preserved functionality of neoplastic tissue for complex tasks. Additionally, tumour locations corresponding to task-responsive electrodes exhibited functional connectivity patterns that significantly co-localised with canonical brain networks implicated in higher-order cognitive processing (p < 0.05). Finally, dorsal attention network connectivity in tumour-infiltrated cortex correlated with high gamma power elevations during increased cognitive demand (χ 2(1) = 5.14; p = 0.023), establishing a concordance between both techniques. Overall, this study contributes convergent evidence that tumour-infiltrated cortex can participate in large-scale neurocognitive circuits, prompting a reconsideration of traditional notions of neoplastic brain tissue.