Cognition and Survival Following Surgical Resection in Patients with High Grade Glioma

Gliomas are one of the most common forms of brain tumour (Weller et al., 2024). They occur in glial cells in the central nervous system and can be classified according to their molecular biomarkers and aggressiveness, with Grade 1 gliomas being the least aggressive and Grade 4 being the most (Louis et al., 2021; Mesfin et al., 2025). The prognosis with gliomas is poor but may be improved with supramaximal resection, removing the tumour and some surrounding tissue (Bush et al., 2017). However, unlike other organs, the brain has limited functional redundancy so removing a wider margin may result in additional cognitive impairments. An alternative to the supramaximal approach is a resection strategy informed by onco-functional balance, which attempts to improve survival whilst maintaining quality of life (Duffau, 2025; Gras-Combe et al., 2012). An onco-functional balance model prioritises the preservation of regions involved in key functional networks even if this leaves cancerous tissue. Whilst this may help conserve cognitive functions, it can worsen prognosis as affected tissue remains, which may increase the likelihood of tumour progression and reduce survival. Our study will investigate whether evidence from a single-centre patient cohort supports onco-functional balance as an approach to high grade glioma treatment.