Diffusely infiltrating IDH-wildtype gliomas tend to have the most aggressive behavior and worst clinical outcomes, and are designated as ‘Glioblastoma, IDH-wildtype’ if they have at least one of the following features: microvascular proliferation, necrosis, EGFR amplification, TERT promoter mutation, and/or simultaneous gain of chromosome 7 and loss of chromosome 10 (+ 7/− 10) [16, 65]. The gene discussed is IDH2; the disease is glioblastoma.