IDH2 and glioblastoma: Across a number of studies, the substantial differences in OS between IDH-mutant and IDH wildtype (IDH-WT) GBM were identified such as 3.8 versus 1.1 years [5], 2.6 versus 1.3 years [8], 2.3 versus 1.2 years [9], and 3 years versus 1 year [13].