We report four cases encountered at two institutions between 2015 and 2020, diagnosed as “Glioblastoma (Astrocytoma), IDH-mutant, WHO grade 4,” found to carry EGFR amplification, an alteration diagnostic of IDH-wildtype Glioblastoma.1 Three patients were adults and one was pediatric. Here, IDH1 is linked to astrocytoma (excluding glioblastoma).