According to the latest World Health Organization (WHO) classification, the terminology for adult diffuse astrocytic tumors has been refined: an IDH-mutated diffuse astrocytoma with grade IV histological features is now termed “astrocytoma, IDH-mutant, WHO grade 4,” whereas the term “glioblastoma” is reserved exclusively for IDH-wild-type cases [6, 7]. The gene discussed is IDH1; the disease is astrocytoma (excluding glioblastoma).