Preliminary Experience of Circular Stapler-based Lower Mediastinal Reconstruction in Robotic Total and Proximal Gastrectomy

Background: In minimally invasive surgery for upper gastric and esophagogastric junction cancers, linear staplers are commonly used, and reports of circular‑stapled reconstruction have declined in parallel with the decrease in open surgery. Lower mediastinal reconstruction during robot‑assisted gastrectomy also remains technically challenging. This study describes our surgical technique and preliminary experience with transhiatal lower mediastinal anastomosis using a circular stapler. Methods: Twelve patients who underwent robot‑assisted total or proximal gastrectomy with lower mediastinal reconstruction between March 2023 and December 2025 were included. Total operative time, blood loss, reconstruction time, length of hospital stay, postoperative complications, and esophageal transection length were evaluated separately for robot‑assisted total gastrectomy (RTG) and robot‑assisted proximal gastrectomy (RPG). Results: No patient required conversion to open surgery. In the RTG group (n=6), the operative time, reconstruction time, blood loss, and hospital stay were 498.0 ± 61.1 minutes, 36.2 ± 8.4 minutes, 175 ± 117.3 g, and 14.3 ± 2.7 days, respectively. In the RPG group (n=6), these values were 345.8 ± 51.5 minutes, 75.6 ± 14.0 minutes, 75.0 ± 98.7 g, and 14.3 ± 2.7 days. Postoperative complications included one anastomotic stricture and one Grade B pancreatic fistula, both in the RPG group. No anastomotic leakage occurred in either group. The esophageal transection length was 35.2 ± 14.0 mm in the RTG group and 25.5 ± 7.9 mm in the RPG group, and all resection margins were negative. Conclusion: Circular staplers are feasible and safe for lower mediastinal reconstruction in robot‑assisted total and proximal gastrectomy.