IDH1 and astrocytoma (excluding glioblastoma): Among the high-grade gliomas, it was noticed in 16% (10/63) of IDH-wt GBM, 17% (1/6) of IDH-mutant astrocytomas (grade 4), 20% (1/5) of IDH-mutant astrocytomas (grade 3), 12% (2/17) of IDH-mutant 1p/19q OG (grade 3), 22% (2/9) of midline H3K27-altered gliomas, and 25% (2/8) of wt diffuse pediatric gliomas.