MGMT and glioblastoma: Well-documented prognostic parameters associated with a favorable outcome in patients with GBM include young age, high preoperative Karnofsky performance status (KPS) score, genetic composition (i.e., isocitrate dehydrogenase [IDH] mutation, O6-methylguanine-DNA methyltransferase [MGMT] promoter methylation), and more extensive surgical resection [3–15].