IDH-mutant astrocytomas with either CDK4 amplifications or CDKN2A deletions had significantly shorter survival (median PFS of 32 months; median OS of 36 months) compared to IDH-mutant astrocytomas without these alterations (median PFS of 95 months, p = 0.02; median OS of >172 months, p = 0.02) [52]. Here, IDH1 is linked to astrocytoma (excluding glioblastoma).