The Role of Neoadjuvant Therapy to Improve the Extent of Resection in Unresectable Gliomas

BACKGROUND: Surgical resection plays a pivotal role in the management of glial tumors and a greater extent of resection (EOR) should be the goal in most surgeries to improve overall survival. Many factors may limit the EOR. A potential role for preoperative chemotherapy to decrease the volume and/or infiltration of gliomas, thereby facilitating a safe radical resection, has been recently suggested. This review aims to provide an overview of the current state of neoadjuvant therapy in the field of glioma surgery. METHODS: A systematic review was conducted according to PRISMA guidelines to identify articles of low- and high-grade gliomas that received neoadjuvant chemotherapy prior to surgery to improve the EOR from 2000 to 2020. Full-text articles that addressed this subject were included for evaluation. - RESULTS: Case reports and clinical trials have been published for the use of chemotherapy as a neoadjuvant therapy to improve surgical resection in low-grade gliomas. More scarce information exists regarding this strategy for high-grade glioma surgery. CONCLUSIONS: Neoadjuvant chemotherapy has played a role in overcoming obstacles that limit the EOR in patients with complex gliomas, especially lowgrade gliomas.

Automated summary

Neoadjuvant chemotherapy has been shown to be effective in improving surgical resection in low-grade gliomas, with limited evidence available for high-grade gliomas. It has played a role in overcoming barriers to greater extent of resection in patients with complex gliomas.