In discussing therapy modalities for IDH mutant gliomas, this review differentiates between low-grade gliomas carrying these mutations as grade 2 oligodendrogliomas and astrocytomas versus IDH mutant high-grade gliomas, which include grade 3 oligodendrogliomas and grades 3 and 4 astrocytomas. Here, IDH1 is linked to astrocytoma (excluding glioblastoma).