Technical nuances of awake brain tumor surgery and the role of maximum safe resection.

Awake craniotomy is a valuable surgical approach to aide in the identification and preservation of functional areas of the brain during the removal of intrinsic brain tumors. We reviewed the current literature for evidence in support of extent of resection to improve survival, symptom management, and time to malignant transformation in low- and high-grade glioma, as well as methods and technical nuances to maximize safety and extent of resection during awake brain tumor surgery. We found 22 studies involving low-grade glioma and 33 studies of high-grade glioma that examined the role of extent of resection to improve outcome. Though there are no randomized clinical trials on the subject, there is a growing body of evidence supporting improved overall and progression-free survival with greater extent of resection. Additionally, patients benefit from longer malignant progression-free survival in addition to superior seizure control. Techniques in awake brain tumor surgery have evolved to allow a greater degree of safety, even in patients who were previously considered high risk. Based on the current practice described in this review, we conclude that awake brain tumor surgery can be safely performed to improve extent of tumor resection and survival, with the added benefit of low failure rates and excellent long-term functional outcomes.