Effect of laparoscopy-assisted vs open surgery on 3-year disease-free survival in patients with low rectal cancer: The LASRE randomized clinical trial.

Abstract

8 Background: Laparoscopic surgery has been increasingly used for low rectal cancer due to short-term benefits versus open surgery, but the long-term oncologic outcomes have not been fully established. Methods: This is a multicenter, noninferiority trial. Surgeons who had completed ≥100 laparoscopic TME surgeries from 22 high-volume centers in China participated in this trial. A total of 1070 patients scheduled for curative-intent resection of low rectal cancer (lower margin <5.0 cm dentate line) were randomized at a 2:1 ratio to undergo laparoscopic or open surgery from November 2013 to June 2018.The primary outcome was 3-year DFS; the noninferiority margin was 10% in the modified intent-to-treat population. Secondary outcomes included 3-year overall survival (OS) and locoregional recurrence. Results: The final analysis included 1039 patients (median age: 57 years, 620 men; 685 and 354 in laparoscopic and open groups, respectively). Clinical TNM stage was II/III in 659 patients, and I in the remaining 380 patients. The 3-year DFS rate was 81.4% in the laparoscopic group versus 79.8% in the open group (HR, 0.9 [95% CI, 0.7 to 1.2]; log-rank P = .558). The absolute difference was 1.6% (1-sided 97.5% CI, -3.34% to ∞), not exceeding the noninferiority . The 3-year OS rate was 91.7% in the laparoscopic group versus 93.7% in the open group (95% CI, -5.12% to1.54%, log-rank P = .243). The 3-year locoregional recurrence rate was 3.8% and 2.4%, respectively (95% CI, -1.07% to 3.45%, log-rank P = .209). Results of the per-protocol and as-treated analysis were consistent with the main analysis. Conclusions: Among patients with low rectal cancer, laparoscopic surgery performed by experienced surgeons is not inferior to open surgery concerning 3-year disease-free survival. These results support laparoscopic surgery as a safe, minimally invasive approach for low rectal cancer. Clinical trial information: NCT01899547 .