By applying the cIMPACT-NOW Update 3 signature, 270 cases were reclassified as “Diffuse astrocytic glioma, IDH-wt, with molecular features of glioblastoma, WHO grade IV” due to the presence of at least one of biomolecular markers that define the cIMPACT-NOW 3 signature. Here, IDH1 is linked to glioblastoma.