Univariable Cox proportional hazards regression analysis identified age ≤ 65y (HR 0.64; 95% CI, 0.51–0.80; p < 0.0001), KPS >70 (HR 0.59; 95% CI, 0.47–0.74; p < 0.0001), MGMT promoter methylation (HR 0.72; 95% CI, 0.57–0.90; p < 0.004), adjuvant chemoradiation (HR 0.14; 95% CI, 0.11–0.19; p < 0.0001), smaller pre-operative CE tumor volumes (per cm3 HR 0.92; 95% CI, 0.83–1.01; p < 0.094), maximal CE tumor resection (HR 0.51; 95% CI, 0.36–0.72; p < 0.0001), and ≥30% NCE tumor resection (HR 0.72; 95% CI, 0.58–0.91; p = 0.005) as being associated with longer overall survival. The gene discussed is MGMT; the disease is cholesteryl ester measurement.