IDH1 and glioblastoma: MGMT was methylated in 46.6%; IDH mutations were prevalent in 5.3% of cases, which is both very similar to values known from literature.16,23,25 This indicates that our cohort is representative for the general population of GBM patients classified by WHO 2007 and 2016 classification which was also used in the mentioned clinical trials and other real-world analysis and is not substantially confounded by selection bias.