Surgical Techniques and Related Perioperative Outcomes After Robot-assisted Minimally Invasive Gastrectomy (RAMIG): Results From the Prospective Multicenter International Ugira Gastric Registry

Objective: To gain insight in global practice of RAMIG and evaluated perioperative outcomes using an international registry. Background: The techniques and perioperative outcomes of robot-assisted minimally invasive gastrectomy (RAMIG) for gastric cancer vary substantially in literature. Methods: Prospectively registered RAMIG-cases for gastric cancer (≥10 per center) were extracted from 25 centers in Europe, Asia and South-America. Techniques for the resection, reconstruction, anastomosis and lymphadenectomy were analyzed, and related to perioperative surgical and oncological outcomes. Complications were uniformly defined by the Gastrectomy Complications Consensus Group. Results: Between 2020-2023, 759 patients underwent total (n=272), distal (n=465) or proximal (n=22) gastrectomy (RAMIG). After total gastrectomy with Roux-en-Y-reconstruction, anastomotic leakage rates were 8% with hand-sewn (n=9/111) and 6% with linear stapled anastomoses (n=6/100). After distal gastrectomy with Roux-en-Y (67%) or Billroth-II-reconstruction (31%), anastomotic leakage rates were 3% with linear stapled (n=11/433) and 0% with hand-sewn anastomoses (n=0/26). Extent of lymphadenectomy consisted of D1+ (28%), D2 (59%) or D2+ (12%). Median nodal harvest yielded 31 nodes [IQR 21-47] after total and 34 nodes [IQR 24-47] after distal gastrectomy. R0-resection rates were 93% after total and 96% distal gastrectomy. Hospital stay was 9 days after total and distal gastrectomy, and was 3 days shorter without perianastomotic drains versus routine drain placement. Postoperative 30-day mortality was 1%. Conclusions: This large multicenter study provided a worldwide overview of current RAMIG-techniques with their respective perioperative outcomes. These outcomes demonstrated high surgical quality, set a quality standard for RAMIG and can be considered an international reference for surgical standardization.