IDH2 and astrocytoma (excluding glioblastoma): New cIMPACT-NOW update 3 clinical guidelines now recommend the diagnosis of “diffuse astrocytic glioma, IDH-wildtype with molecular features of glioblastoma“, for IDH wildtype astrocytomas lacking the histologic features of glioblastoma but having one or more of these “molecular grade IV” features [130], and this has been confirmed in subsequent validation studies [131].