Fig 1.

A model for molecular classification of diffuse gliomas in adults. Alterations in IDH lead the TP53-ATRX-mutation pathway or the 1p/19q-codeletion-CIC/FUBP1-mutation pathway. Pathologically, the former corresponds to diffuse astrocytoma whereas the latter to classic oligodendroglioma. Non-classic oligodendrogliomas and oligoastrocytomas typically lack IDH mutation or other genetic signatures. Primary glioblastoma does not have either genetic signature and is likely underlaid by multiple molecular pathways. ATRX: alpha-thalassemia/mental retardation syndrome X-linked, CIC: capicua homolog, codel: codeletion, FUBP1: far upstream element binding protein 1, IDH: isocitrate dehydrogenase, mt: mutation, OLG: oligodendroglioma, wt: wild type.