IDH1 and astrocytoma (excluding glioblastoma): In non-TCGA IDH1/2-mutant astrocytomas, CCND2 alteration (HR: 3.05), EGFR amplification (HR: 2.43), CDKN2A/B loss (homozygous or heterozygous loss, HR: 2.28), 22q loss (HR: 1.97), and PDGFRA alteration (HR: 1.92) were negatively prognostic (Figure 4D).