Long-Term Oncologic Outcomes After Laparoscopic Versus Open Resection for Colorectal Liver Metastases : A Randomized Trial.

ABSTRACT

BACKGROUND: Despite the recent worldwide dissemination of laparoscopic liver surgery, no high-level evidence supports the oncologic safety of this approach. OBJECTIVE: To evaluate long-term oncologic outcomes after laparoscopic versus open liver resection in patients with colorectal metastases. DESIGN: A single-center, assessor-blinded, randomized controlled trial (OSLO-COMET [Oslo Randomized Laparoscopic Versus Open Liver Resection for Colorectal Metastases Trial]). (ClinicalTrials.gov NCT01516710). SETTING: Oslo University Hospital, the only provider of liver surgery for the 3 million inhabitants of southeastern Norway. PARTICIPANTS: Patients with resectable colorectal liver metastases were randomly assigned to have open or laparoscopic liver resection. INTERVENTION From February 2012 to January 2016, a total of 280 patients were included in the trial (laparoscopic surgery n = 133; open surgery n = 147). MEASUREMENTS The primary outcome was postoperative morbidity within 30 days. Five-year rates of overall and recurrence-free survival were predefined secondary end points. RESULTS: At a median follow-up of 70 months, rates of 5-year overall survival were 54% in the laparoscopic group and 55% in the open group (between-group difference, 0.5 percentage point [95% CI, -11.3 to 12.3 percentage points]; hazard ratio, 0.93 [CI, 0.67 to 1.30]; P = 0.67). Rates of 5-year recurrence-free survival were 30% in the laparoscopic group and 36% in the open group (between-group difference, 6.0 percentage points [CI, -6.7 to 18.7 percentage points]; hazard ratio, 1.09 [CI, 0.80 to 1.49]; P = 0.57). LIMITATION: The trial was not powered to detect differences in secondary end points and was not designed to address a noninferiority hypothesis for survival outcomes. CONCLUSION: In this randomized trial of laparoscopic and open liver surgery, no difference in survival outcomes was found between the treatment groups. However, differences in 5-year overall survival up to about 10 percentage points in either direction cannot be excluded. This trial should be followed by pragmatic multicenter trials and international registries. PRIMARY FUNDING SOURCE The South-Eastern Norway Regional Health Authority.