Robotic intracorporeal single-stapling versus double-stapling anastomosis in left-sided colorectal cancer: a propensity score-weighted pilot study

Abstract

Colorectal cancer remains a major cause of cancer-related deaths worldwide. Surgical resection is still the mainstay treatment for malignancies situated in the left colon and rectum. Selection of the anastomosis method significantly affects patient recovery and the likelihood of postoperative complications. In this pilot study, we compare early clinical results between two robotic anastomosis techniques, intracorporeal single-stapling (RiSSA) and extracorporeal double-stapling (DSA), used in robotic surgeries for left-sided colorectal cancer.A total of 49 consecutive patients underwent curative-intent robotic procedures at a tertiary academic hospital in Kaohsiung, Taiwan, from May 2023 to February 2025. Of these, 31 patients received the RiSSA technique, while 18 underwent DSA for anastomosis. Baseline differences were accounted for using inverse probability of treatment weighting (IPTW). Patients undergoing RiSSA experienced shorter surgery times, faster gastrointestinal recovery, reduced hospital stays, and fewer diverting stomas. While the RiSSA group had a lower anastomotic leakage rate (0% compared to 9.5%), this difference did not reach statistical significance. Additional sensitivity analyses reinforced the robustness of the findings. Despite inherent limitations, such as its retrospective design, modest sample size, selection bias, and possible operator learning curve, this exploratory analysis supports the notion that RiSSA may represent a viable and safe alternative to conventional extracorporeal techniques, with potential benefits in short-term postoperative outcomes. Further prospective studies are required to validate these initial findings.

Keywords: Colorectal cancer; Minimally invasive surgery; Robotic colorectal surgery; Single-stapling anastomosis.