Moy02 ten years of robot-assisted versus laparoscopic total mesorectal excision for rectal cancer (long-term RESOLUTION): an international, multicentre, retrospective propensity score-weighted cohort study of long-term oncological outcomes

Aims: Total mesorectal excision is the standard surgical treatment for rectal cancer surgery, with both laparoscopic and robot-assisted approaches frequently utilised. Although robot-assisted surgery may offer technical advantages, data comparing the long-term outcomes of these techniques is limited, especially in Western populations. This study aimed to compare the long-term oncological outcomes of laparoscopic and robot-assisted total mesorectal excision for rectal cancer.

Methods: This retrospective, multicentre, international cohort study included 1077 rectal cancer patients who underwent either laparoscopic or robot-assisted total mesorectal excision between 2014 and 2021, with at least three years of follow-up. Inverse probability of treatment weighting was applied to minimize confounding. The primary outcomes were three-year oncological endpoints, including disease-free survival, overall survival, local recurrence, and systemic recurrence.

Results: After weighting, 435.8 laparoscopic and 637.4 robot-assisted cases were analysed. Robot-assisted total mesorectal excision was associated with improved mesorectal excision quality (76.5% vs. 87.5%, p<0.001), but no significant differences were observed in circumferential resection margin positivity, conversion rates, or postoperative complications. Additionally, there were no significant differences in three-year disease-free survival (75.1% vs 75.2%, HR 1.04, CI 0.80-1.34), overall survival (81.6% vs 81.7%, HR 1.14, CI 0.80-1.61), local recurrence (3.7% vs 3.0%, HR 0.89, CI 0.45-1.80), or systemic recurrence (15.1% vs 15.3%, HR 0.97, CI 0.69-1.34).

Conclusion: Robot-assisted surgery offers a safe, minimally invasive alternative to laparoscopic surgery, providing comparable three-year oncological outcomes. These findings support its continued use as a viable option for rectal cancer surgery, especially in centres with expertise in robotic techniques.