The Weight of Eloquence in Motor Area Glioblastoma: Oncologic Outcome After nTMS-Guided Surgical Resection

Glioblastomas (GBMs) in eloquent areas, particularly within the motor system, represent a significant surgical challenge due to the risk of postoperative neurological deficits. This study evaluates the effectiveness of a structured preoperative protocol, including nTMS-guided motor mapping, to optimize surgical outcomes and minimize neurological deficits, with a particular focus on the timing of adjuvant oncological therapy initiation.

A retrospective analysis was conducted on 44 GBM patients, divided into two groups: 11 with motor area lesions (group A) and 33 with non-eloquent lesions (group B). All patients underwent a standardized preoperative protocol. Surgical outcomes (EORs), neurological function (MRC score and KPS index), time to oncological therapy initiation and survival (OS and PFS) were compared between groups.

Both groups achieved high rates of GTR without significant differences in EOR (72.7% group A vs. 78.8% group B). Although group A exhibited a higher incidence of postoperative motor deficits, motor function at three-month follow-up was similar between groups. Time to initiation of oncological therapy did not differ between groups (40.6 days group A vs. 41.9 days group B, p = 0.719), highlighting that preservation of motor function helped minimize delays in starting oncological therapy. No significant differences were found in survival outcomes.

A structured preoperative protocol incorporating nTMS motor mapping allows for safe and aggressive resection of motor-area GBMs. This approach effectively mitigates the risk of delays in initiating adjuvant oncological therapy, optimizing the patient prognosis. Further studies are needed to explore the long-term benefits of this protocol in both functional and oncological outcomes.