MGMT and neoplasm: For PFS, the following factors were significantly associated in the multivariable Cox regression analysis (Figure 3): GTR versus biopsy only (HR: 0.19, p = 0.026), pRT versus no pRT (HR: 0.36, p = 0.006), postoperative TMZ‐based chemotherapy versus no postoperative chemotherapy (HR: 0.39, p < 0.001), MGMT promoter status unknown versus methylated (HR: 1.69, p = 0.034), and tumor diameter per cm (HR: 1.18, p = 0.016).