Based on the molecular characteristics, particularly isocitrate dehydrogenase (IDH) status, adult-type diffuse gliomas are categorized into glioblastoma (IDH-wildtype), astrocytoma (IDH-mutant), and oligodendroglioma (IDH-mutant and 1p/19q-codeleted) [1]. Here, IDH2 is linked to astrocytoma (excluding glioblastoma).