E-ISSN: 1019-5157 ISSN: 2651-5024
Research

Functional Mapping-Guided Resection of Eloquent Diffuse Low-Grade Gliomas: A Single-Institution Experience from a Low-Middle Income Country

Seif Tarek El-Swaify , Ahmed Maamoun Ashour , Mohamed Mostafa Aziz , Ashraf Gamal Al-Abyad
DOI: 10.5137/1019-5149.JTN.49066-25.2 Article in Press

Abstract

Aim
There are logistical barriers to achieving onco-functional balance through glioma surgery in low- and middle-income countries (LMICs). We report our experience in implementing functional mapping-guided resection for eloquent diffuse low-grade gliomas (DLGGs) in an LMIC setting.

Material and Methods
The study is a retrospective chart review of adult patients who underwent surgical resection of their DLGGs that were located within supratentorial eloquent brain areas (within 15 mm). Functional mapping-guided surgery was performed using electrophysiological brain mapping techniques, namely intraoperative neuromonitoring (IONM) with or without awake craniotomy (AC). The primary outcome was the rate of postoperative neurological deficits. The secondary outcomes were the extent of resection, the rate of surgical complications, the Engel Outcome Scale score, and the progression-free survival (PFS) rate.

Results
Twenty-eight patients were included (43% males), with a mean age of 37.5 years. Their median preoperative Karnofsky Performance Scale score was 90. The predominant histopathology was astrocytoma (n = 20, 71%), and the primary site was perirolandic in 19 patients (68%). Seizures were the most common presenting symptom (71%). Resection was performed using either IONM alone (39%) or combined with AC (61%). Gross total resection was achieved in 20 patients. Six patients (21%) developed postoperative complications. Patients were followed up for a mean of 39.9 months. At discharge, 12 patients (43%) had experienced new or worsened neurological deficits, but nine of them later showed significant improvement. Sixteen patients achieved Engel class 1 seizure control, and the median PFS was 34 months. Two patients died during the study period.

Conclusion
This study demonstrates that our institution’s protocol for integrating functional mapping into the surgical management of DLGGs achieves a solid onco-functional balance.

Keywords

Awake surgery Brain mapping Extent of resection Low-grade glioma Neuro-oncology