Robot-assisted versus laparoscopic surgery for rectal cancer: a systematic review and meta-analysis of randomised trials with GRADE certainty rating.

BACKGROUND: Robot-assisted rectal cancer surgery is being adopted rapidly, yet prior meta-analyses have emphasised intermediate endpoints and have not rated the certainty of evidence. We compared the two approaches using a strictly randomised evidence base, with formal certainty rating and robustness testing. METHODS: We searched PubMed/MEDLINE, Embase and Cochrane CENTRAL from inception to 28 March 2026 for randomised controlled trials. Pre-specified primary outcomes were total operative time and major complications (Clavien-Dindo grade ≥ III). Outcomes were pooled using random-effects models with restricted maximum likelihood estimation and Hartung-Knapp-Sidik-Jonkman confidence intervals; risk of bias was assessed per outcome (RoB 2) and certainty rated with GRADE (PROSPERO CRD420261383724). RESULTS: Seven independent trials (2,540 patients) were synthesised. Robot-assisted surgery was associated with longer operative time (MD 39.8 min, 95% CI 4.4 to 75.3) and fewer conversions (OR 0.52, 0.30 to 0.91), with no difference in major complications (OR 0.69, 0.36 to 1.31). Estimates favouring robot-assisted surgery for circumferential margin positivity (OR 0.62, 0.37 to 1.05) and complete mesorectal excision (OR 1.47, 0.92 to 2.36) were not significant and attenuated when the largest trial was excluded. Disease-free and overall survival did not differ. Certainty was low or very low throughout. One trial judged robot-assisted surgery not cost-effective; none reported environmental outcomes. CONCLUSIONS: Current randomised evidence does not establish clear overall superiority of robot-assisted over laparoscopic rectal cancer surgery, despite fewer conversions, and indicates higher direct costs where reported. These largely confirmatory findings suggest outcomes depend more on patient and surgeon factors than on the platform. TRIAL REGISTRATION: PROSPERO (CRD420261383724).