Comparison of Outcomes between Supramaximal Resection and Gross Total Resection for High-Grade Gliomas: A Prospective Study from a Tertiary Care Centre

High-grade gliomas (HGG), including glioblastomas and anaplastic gliomas, are among the most aggressive primary brain tumors with poor prognosis despite multimodal treatment. Surgical resection remains the cornerstone of management, with gross total resection (GTR) traditionally considered the standard operative goal. However, recent evidence supports supramaximal resection (SMR)—removal of the enhancing tumor along with a margin of infiltrating non-enhancing tumor—as a strategy that may improve progression-free survival and overall survival (OS) without significantly increasing neurological morbidity. Fifty-six adult patients with histologically confirmed Grade 3 or 4 gliomas undergoing surgical resection between January 2024 and May 2025 were enrolled. Patients underwent either SMR (n = 27) or GTR (n = 29) based on predefined anatomical and functional criteria. Detailed clinical, radiological, perioperative, and follow-up data were collected, including Karnofsky Performance Scores (KPS), length of hospital stay, complications, adjuvant therapy administration, recurrence rates, and survival outcomes. Statistical analyses compared these parameters between groups. The cohort had a mean age of 47.6 years, with a male predominance (69.6%). Histopathology distribution showed 46.4% glioblastomas, 25% astrocytomas, and 23.2% oligodendrogliomas. Preoperative and postoperative KPS scores were higher in the SMR group though differences were not statistically significant (p = 0.124 and p = 0.094, respectively). The SMR group had a trend toward shorter hospital stay (11.07 vs. 13.65 days, p = 0.11) and longer surgical duration (296 vs. 283 minutes, p = 0.51) compared with GTR but without significance. Postoperative complication rates were comparable (SMR 11%, GTR 24%). Recurrence was lower in the SMR group (7.4%) versus GTR (27.6%). Mortality rates were 25.9% for SMR and 44.8% for GTR, corresponding to OS rates of 74.1% (SMR) and 55.2% (GTR). Adjuvant radiotherapy and chemotherapy were administered similarly between groups, without statistically significant differences. SMR appears to offer improved oncological outcomes in terms of recurrence and survival compared with GTR for HGG in this cohort, without increased perioperative morbidity. The findings support consideration of SMR as a safe and potentially more effective surgical strategy for appropriately selected patients, emphasizing the importance of functional preservation and modern intraoperative guidance.