Impact of the articulating robotic system on suprapancreatic lymphadenectomy in obese patients with gastric cancer: A comparative study with conventional laparoscopy

Obesity complicates lymph node dissection (LND) during gastric cancer surgery, particularly in deep anatomical zones. While robotic gastrectomy (RG) offers ergonomic advantages, its impact on the technically demanding suprapancreatic area in obese patients remains unclear. This study compared LND quality between RG and laparoscopic gastrectomy (LG) in obese patients.We retrospectively analyzed 404 patients who underwent LG (n = 319) or RG (n = 85) for gastric cancer. Patients were stratified by body mass index (BMI) (non-obese < 25 kg/m2 vs. obese ≥ 25 kg/m2). We assessed retrieved lymph nodes in the suprapancreatic area (stations 7, 8a, 9) and perigastric area (stations 1–6). Two-way analysis of variance (ANOVA) assessed the effects of BMI and surgical approach.In the perigastric area, obesity was an independent risk factor for decreased lymph node yields (p = 0.033), with no significant difference between RG and LG (p = 0.50). Conversely, in the suprapancreatic area, the robotic approach was a strong independent factor for increased retrieval (p < 0.001). Pairwise comparisons showed that obesity significantly reduced yields in the LG group (total: p = 0.012; suprapancreatic: p = 0.015), while the RG group maintained consistently high yields regardless of BMI (p = 0.371 and p = 0.857, respectively).The robotic approach was associated with superior, more consistent suprapancreatic LND, whereas obesity negatively affected perigastric retrieval regardless of platform. These findings suggest that robotic articulation may help maintain the quality of suprapancreatic lymphadenectomy in obese patients.