IDH1 and oligodendroglioma: In the intricate landscape of adult-type diffuse gliomas, distinctions arise among IDH-mutant and 1p/19q-non codeleted astrocytoma (IDH-A), IDH-mutant and 1p/19q-codeleted oligodendroglioma (IDH-O), and IDH-wildtype glioblastoma (IDH-wt) [3].