Robotic versus Laparoscopic Intersphincteric Resection for Low Rectal Cancer: A Comparative Study of Short-term Outcomes

Abstract

Purpose: Intersphincteric resection (ISR) is a surgical option to preserve the anal sphincter for treatment of low rectal cancer. Laparoscopic ISR has been reported to be technically challenging. The Aim of this study was to assess the short-term outcomes of robotic ISR compared with a laparoscopic approach. Methods: Ninety four consecutive patients who underwent laparoscopic (n=60) or robotic (n=34) ISR with hand-sewn coloanal anastomosis for low rectal cancer from January 2011 to December 2014 were included. Patient demographics, operative data, and histopathologic and postoperative outcomes were analyzed. Results: There were no differences in demographic data including tumor location, which was 2.5±0.7㎝ from the anal verge in the laparoscopic group and 2.7±0.9 ㎝ in the robotic group. Mean operation time was significantly longer in the robotic group compared with the laparoscopic group (278±65.3 minutes versus 225±66.9, p＜0.001). With respect to histopathologic outcomes, patients with circumferential resection margin (CRM) less than 2 ㎜ were observed more frequently in the laparoscopic group than in the robotic group (18.3% versus 5.9%, p=0.050). The rate of postopeative morbidity was lower in the robotic group than in the laparoscopic group (14.7% versus 35.0%, p=0.035). Patients in the robotic group showed a low Clavien-Dindo score more frequently than those in the laparoscopic group (p=0.049). Conclusion: Robotic ISR is a safe and feasible procedure associated with a lower rate of narrow CRM and postoperative morbidity in spite of a longer operation time, compared with the laparoscopic approach. Prospective clinical trials with larger numbers of cases evaluating long-term oncologic and functional outcomes are required.