A multivariate model that incorporated age, grade, treatment and loss of CDKN2A/B showed that in the group of astrocytomas, concomitant TERT promoter and IDH mutations indicate good survival (HR = 0.02; 95% HR CI 0.001 – 0.542; P = 0.02) whereas TERT promoter mutations alone associated with poor survival (HR = 37.7; 95% HR CI 1.63 – 870.8; P = 0.02) (Supplementary Table 4). Here, IDH1 is linked to astrocytoma (excluding glioblastoma).