Operative efficiency and short-term outcomes of da Vinci 5 versus da Vinci Xi in robotic rectal cancer surgery: an overlap-weighted cohort study with an exploratory case insights analysis

The da Vinci 5 introduces changes in operative workflow and instrument control, but its comparative performance in rectal cancer surgery remains uncertain. We compared operative efficiency and short-term outcomes after platform introduction and explored platform-derived intraoperative measurements. This retrospective single-center study included 202 patients undergoing robot-assisted rectal cancer surgery from July 2025 to September 2026 (Xi, n = 109; da Vinci 5, n = 93). Propensity-score overlap weighting addressed measured differences. The primary outcome was total operative time. HC3 inference was checked using 2,000 bootstrap replicates with propensity-score re-estimation. Retrieved Case Insights records were summarized descriptively. The adjusted difference in total operative time was − 6.9 min (HC3 95% confidence interval [CI], − 24.4 to 10.6; P = 0.439); the bootstrap 95% CI was − 21.8 to 7.8 min. The adjusted risk difference for Clavien–Dindo grade ≥ II complications was − 9.4% points (HC3 95% CI, − 19.8 to 0.9; P = 0.074). Margin positivity occurred in only three patients and was reported descriptively. Inference for postoperative hospital stay depended on the variance method. We did not detect a statistically clear reduction in total operative time after the introduction of the da Vinci 5. Secondary outcomes remain exploratory. Exploratory Case Insights analysis provided descriptive information on instrument-tip force and surgical workflow, warranting further prospective validation of their clinical relevance.