Comparison between robotic-assisted and laparoscopic sphincter-preserving operations for ultra-low rectal cancer: a single institutional retrospective study

Abstract

Background Sphincter-preserving operations for ultra-low rectal cancer include low anterior resection and intersphincteric resection. In low anterior resection, the distal rectum is divided by a transabdominal approach, which is technically demanding. In intersphincteric resection, a perineal approach is performed. We aimed to evaluate whether robotic-assisted surgery is technically superior to laparoscopic surgery for ultra-low rectal cancer. The frequency of conducting low anterior resection by a specific procedure can indicate the technical superiority of that procedure for ultra-low rectal cancer. Thus, we compared the frequency of low anterior resection between robotic-assisted and laparoscopic surgery in cases of sphincter-preserving operations. Methods We investigated 183 patients who underwent sphincter-preserving robotic-assisted or laparoscopic surgery for ultra-low rectal cancer (lower border within 5 cm of the anal verge) between April 2010 and March 2020. The frequency of low anterior resection was compared between laparoscopic and robotic-assisted surgeries. The clinicopathological factors associated with an increase in performing low anterior resection were analyzed by multivariate analyses. Results Overall, 41 (22.4%) and 142 (77.6%) patients underwent laparoscopic and robotic-assisted surgery, respectively. Patient characteristics were similar between the groups. Low anterior resection was performed significantly more frequently in robotic-assisted surgery (67.6%) than in laparoscopic surgery (48.8%) (p = 0.04). Multivariate analyses showed that tumor distance from the anal verge (p < 0.01) and robotic-assisted surgery (p = 0.02) were significantly associated with an increase in the performance of low anterior resection. The rate of postoperative complications or pathological results was similar between the groups. Conclusions Compared with laparoscopic surgery, robotic-assisted surgery significantly increased the frequency of low anterior resection in sphincter-preserving operations for ultra-low rectal cancer. Robotic-assisted surgery has technical superiority over laparoscopic surgery for ultra-low rectal cancer treatment.