MGMT and neoplasm: Patients with lower MGMT mRNA expression showed significantly poorer OS (mOS 20.4 vs 31.7 months, unadjusted HR 1.89; 95% CI 1.01–3.56; P = 0.043), which was confirmed in a multivariable model accounting for patients' age, gender, and primary tumor location, prior tumor resection and use of adjuvant therapy (Fig. 3A and Table S4).