Role of surgical resection in low- and high-grade gliomas.

OPINION STATEMENT: Central nervous system tumors are a major cause of morbidity and mortality in the United States. Outside of brain metastasis, low- and high-grade gliomas are the most common intrinsic brain tumors. Low-grade gliomas have a 5- and 10-year survival rate of 97 % and 91 %, respectively, when extent of resection is greater than 90 %. High-grade gliomas are extremely aggressive with the vast majority of patients experiencing recurrence and a median survival of 1 to 3 years. Survival of patients with both low- and high-grade gliomas is enhanced with maximal tumor resection. The pursuit of more aggressive extent of resection must be balanced with preservation of functional pathways. Several innovations in neurosurgical oncology have expanded our understanding of individualized patient neuroanatomy, physiology, and function. Emerging imaging technologies as well as intraoperative techniques have expanded our ability to resect maximal amounts of tumor while preserving essential function. Stimulation mapping of language and motor pathways is well-established for the safe resection of intrinsic brain lesions. Additional techniques including neuro-navigation, fluorescence-guided microsurgery using 5-aminolevulinic acid, intraoperative magnetic resonance imaging, and high-frequency ultrasonography can all be used to improve extent of resection in glioma patients.