Fig. 4.

Overall survival after perioperative period (91 days–5 years). HR hazard ratio, CI two-sided 95% confidence interval. A Kaplan–Meier analysis over all stages: 5-year cumulative overall survival rate open versus laparoscopic: 72.5 versus 82.5%, p < 0.001. B Multivariate Cox regression analysis over all stages, adjustment for age, previous carcinomas, synchronous carcinomas, location, grading, TNM stage, hospital classification, resection group, and pre- and postoperative therapy; reference: open approach. C Kaplan–Meier analysis over stage I patients: 5-year cumulative overall survival rate open versus laparoscopic: 82.7 versus 91.4%, p = 0.047. D Multivariate Cox regression analysis over stage I patients, adjustment for age, previous carcinomas, synchronous carcinomas, location, grading, hospital classification, resection group, and pre- and postoperative therapy; reference: open approach. E Kaplan–Meier analysis over stage II patients: 5-year cumulative overall survival rate open versus laparoscopic: 70.6 versus 79.3%, p = 0.052. F Multivariate Cox regression analysis over stage II patients, adjustment for age, previous carcinomas, synchronous carcinomas, location, grading, hospital classification, resection group, and pre- and postoperative therapy; reference: open approach. G Kaplan–Meier analysis over stage III patients: 5-year cumulative overall survival rate open versus laparoscopic: 67.9 versus 79.8%, p = 0.010. H Multivariate Cox regression analysis over stage III patients, adjustment for age, previous carcinomas, synchronous carcinomas, location, grading, hospital classification, resection group, and pre- and postoperative therapy; reference: open approach