Evaluation of this marker is becoming an essential part of the routine diagnosis for diffuse astrocytic tumors with wildtype IDH. The bivalent impact of TERT promoter mutations on glioma biology depends on the IDH status, as such, we have previously proposed a molecular classification based on the IDH and TERT status, which can efficiently identify diffuse astrocytomas and oligodendrogliomas [6]. The gene discussed is IDH1; the disease is oligodendroglioma.