IDH1 and oligodendroglial tumor: Consistent with previous reports [5], oligodendroglial tumors (10 mutations out of 10 tumors: 100%) and IDH-wildtype GBM (7 mutations out of 11 tumors: 63.6%) possessed high incidence of TERT promoter mutations whereas no astrocytic tumors with IDH mutations showed them (Figure 1(c)).