Protocol digest of a phase III randomized trial of gross total resection versus possible resection of fluid-attenuated inversion recovery-hyperintense lesion on MRI for newly diagnosed supratentorial glioblastoma: JCOG2209 (FLAMINGO).

The goal of surgery for patients with newly diagnosed glioblastoma (GBM) is maximum safe resection of the contrast-enhancing (CE) lesion on magnetic resonance imaging. However, there is no consensus on the efficacy of FLAIRectomy, which is defined as the possible resection of fluid-attenuated inversion recovery (FLAIR)-hyperintense lesions surrounding the CE lesion. Although retrospective analyses suggested the potential benefits of FLAIRectomy, such outcomes have not been confirmed by prospective studies. Therefore, we planned a multicenter, open-label, randomized controlled phase III trial to evaluate the efficacy of FLAIRectomy compared with gross total resection of CE lesions in patients with newly diagnosed GBM. The primary endpoint is overall survival. In total, 130 patients will be enrolled from 47 institutions over 5 years. This trial has been registered at the Japan Registry of Clinical Trials (study number jRCT1031230245).