IDH2 and glioblastoma: While this subtype is rare and accounts for approximately 2% of all IDH-wildtype glioblastomas based on the current 2021 WHO Classification definition, we believe that it warrants recognition as a distinct subtype moving forward given both the unique underlying biology and the more favorable prognosis with potential benefit from immune checkpoint blockade suggested by this study and prior case reports [7, 20, 24].