Based on the 2016 WHO classification, 80 patients (52.3%) had diffuse astrocytoma, IDH-mutant; 45 (29.4%) had oligodendroglioma, IDH-mutant and 1p/19q-codeleted (ODG); and 28 (18.3%) had diffuse astrocytoma, IDH-wildtype. The gene discussed is IDH1; the disease is oligodendroglioma.