Long-term oncologic outcomes after laparoscopic versus open rectal cancer resection: a high-quality population-based analysis in a Southern German district

An increasing number of rectal carcinoma resections in Germany and worldwide are performed laparoscopically. The recently published COLOR II trial demonstrated the oncologic safety of this surgical approach. It remains unclear whether these findings can be transferred to clinical practice. This population-based retrospective cohort study aimed to evaluate 5-year overall, relative, disease-free, and local recurrence-free survival of rectal cancer patients treated by open surgery and laparoscopy. Data from a southern German region of 1.1 million inhabitants were collected by an official clinical cancer registry. All primary non-metastatic rectal adenocarcinoma cases with surgery between 2004 and 2013 were eligible for inclusion. To compare survival rates, Kaplan-Meier analyses, relative survival models, and multivariate Cox regression were applied; a sensitivity analysis assessed bias by exclusion. Finally, 1507 patients with a median follow-up time of 7.1 years were included. Of these patients, 28.4% underwent laparoscopic procedures, with an increasing rate over time. Patients with tumors of the upper or middle rectum, younger patients, and patients of specialized colorectal cancer centers were more likely to undergo laparoscopy. After 5 years, 80.4% of laparoscopy patients were still alive, compared to 68.6% in the open group (p < 0.001). Moreover, laparoscopy was associated with superior local recurrence-free survival rates. This advantage was also significant in multivariate analysis (HR 0.70, 95% CI 0.52-0.92). Laparoscopic rectal cancer surgery can be considered safe in daily clinical practice. This should be confirmed by future studies outside the setting of randomized trials.