Cox regression
A radiation dose of 50 Gy or higher appeared as the best prognostic factor with a HR of 0.3 (95% CI: 0.2–0.5), followed by surgery (HR = 0.4, 95% CI: 0.2–0.8) (Table Survival analysis comparing therapy modalities using cox proportional hazard modelsBold values identify significant results with Modell 1: Multivariate analysis with age and sexModell 2: Multivariate analysis with age, sex and Karnofsky scaleModell 3: Multivariate analysis with surgery, chemotherapy, radiation dose, age, sex, Karnofsky scaleR = Hazard Ratio, CI = Confidence Interval*