IDH1 and central nervous system cancer: As for the NT-1 glioma cluster, it was composed of a majority of IDH-mutated gliomas: 80/168 samples, 47.6% for IDH-mutated gliomas with the 1p/19q co-deletion; 67/168 samples, 39.9% for IDH-mutated gliomas without the 1p/19q co-deletion; and 21/168 samples, 12.5% for IDH-wt gliomas.