Comparison of the quality of total mesorectal excision after robotic and laparoscopic surgery for rectal cancer: a multicenter, propensity score-matched study

Purpose: This study aimed to evaluate and compare the quality of total mesorectal excision (TME) and disease-free and overall survival rates between robotic and laparoscopic surgeries for rectal cancer. Methods: From January 2015 to December 2018, 234 patients underwent curative robotic or laparoscopic surgery for rectal cancer at two centers. Ultimately, 201 patients were enrolled. To control for different demographic factors in the two groups, propensity score matching was used at a 1:1 ratio. Propensity scores were generated with the baseline characteristics, including age, sex, body mass index, American Society of Anesthesiologists score, previous abdominal surgery, tumor location, preoperative chemotherapy, and preoperative radiation. Finally, 134 patients were matched with 67 patients in the robotic surgery group and 67 patients in the laparoscopic surgery group. Results: There was no significant difference in the pathologic stages between the robotic and laparoscopic surgery groups. Distal margin involvement was only observed in the robotic surgery group (1/67, 1.5%). Circumferential resection margin involvement was not different between the robotic surgery and laparoscopic surgery groups (3/67 [4.5%] and 4/67 [6.0%], respectively, P=1.000). The quality of TME (complete, nearly complete, and incomplete) was similar between the robotic surgery and laparoscopic surgery groups (88.0%, 6.0%, 6.0% and 79.1%, 9.0%, 11.9%, respectively, P=0.358). The disease-free and overall survival rates were not significantly different between the groups. Conclusion: The quality of TME and disease-free and overall survival rates between the two surgeries were similar. There was no oncologic advantage of robotic surgery for rectal cancer compared to laparoscopic surgery.