All tumors had a histopathologically confirmed diagnosis of GBM according to the World Health Organization classification system, and all tumors had no mutation in IDH1. Expression of O(6)-methylguanine-DNA methyltransferase (MGMT) and the Ki-67 SI in the core of the tumors in the 13 patients are summarized in Suppl. Here, MKI67 is linked to glioblastoma.