EGFR amplification occurs in 40–50% of morphologically defined glioblastoma, IDH wildtype and in a subset of what had previously been classified as IDH-wildtype lower-grade (grade 2 or 3) diffuse astrocytomas (16) which are currently classified as molecular glioblastomas, if they have certain molecular alterations, such as EGFR amplification, TERT promoter mutation and/or +7/−10 signature that confer them a prognosis similar to that of classical glioblastoma (5). The gene discussed is IDH1; the disease is glioblastoma.