In general, grade II and III astrocytomas are 1p/19q non-deleted and either IDH-1 (isocitrate dehydrogenase-1) wild type or mutant, whereas grade II and III oligodendrogliomas are 1p/19q co-deleted and IDH-1 mutant [6, 7]. Here, IDH1 is linked to astrocytoma (excluding glioblastoma).