IDH1 and oligodendroglioma: Amongst all patients ≥20 years old with primary gliomas, the median survival varied across glioblastoma (18.0 months, range: 0.1–164.0 months), IDH1/2-mutant astrocytoma (118.5 months, range: 0.1–262.2 months), and oligodendroglioma (213.9 months, range: 0.1–324.4 months).