IDH2 and oligodendroglioma: In addition to IDH1 or IDH2 mutations and 1p19q codeletion, oligodendrogliomas frequently present mutations of TERT (96%), CIC (Capicua Transcriptional Repressor, 62%), FUBP1 (Far Upstream Element Binding Protein 1, 29%), and/or PI3K (phosphoinositide 3-kinase, 20%) with overexpression of NOTCH1 (Notch homolog 1, translocation-associated, 31%) genes (16).