Assessment of the safety and efficacy of robotic versus laparoscopic gastrectomy in overweight patients with gastric cancer: a large-scale multicenter cohort study

Background: The comparative efficacy of robotic (RG) and laparoscopic gastrectomy (LG) in patients with gastric cancer with a body mass index (BMI) ≥ 25 kg/m² remains unclear. We compared the outcomes between RG and LG in this patient population. Methods: This multicenter cohort study included 695 patients with gastric cancer with BMI ≥ 25 kg/m² who underwent RG (n = 220) or LG (n = 475) at eight high-volume teaching hospitals in China. To reduce intergroup differences, overlap weighting (OW) and inverse probability of treatment weighting (IPTW) were applied. The primary end-points were short-term outcomes, 3-year survival, and recurrence. Results: After OW and IPTW adjustments, the two groups’ baseline characteristics were well-balanced. Intraoperative blood loss, major bleeding rates, number of perioperative transfusions, and incidence of medical complications were lower, while operative time and costs were greater in the RG than LG group (all P < 0.05). Postoperative pneumonia rates tended to be lower in the RG group. The 3-year disease-free survival (DFS) or overall survival (OS) were comparable between groups. Subgroup analyses revealed no statistically significant interactions between the surgical approach and DFS or OS across all variables (all interactions, P > 0.05). Recurrence rates and patterns were comparable between the groups (all P > 0.05). Conclusion: For patients with gastric cancer with BMI ≥ 25 kg/m², RG offers superior short-term outcomes compared to LG, while demonstrating non-inferior 3-year oncological outcomes. RG is a safe and effective surgical approach for managing gastric cancer in patients with elevated BMI.