Surgical outcomes and learning curve analysis of robotic gastrectomy for gastric cancer: Multidimensional analysis compared with three‑dimensional high‑definition laparoscopic gastrectomy.

The present ambispective cohort study was performed to compare the short‑term surgical outcomes, including financial cost and surgeons' acceptance, of robotic versus three‑dimensional high‑definition (3D‑HD) laparoscopic gastrectomy for patients with gastric cancer (GC). Between 2011 and 2017, 517 patients with GC were enrolled for treatment with either robotic gastrectomy [408 patients, including 73 treated by one of the authors (LC)] or 3D‑HD laparoscopic gastrectomy (109 patients, including 71 treated by LC). The cumulative summation method was developed to analyze the learning curves of robotic and 3D‑HD laparoscopic gastrectomy performed by LC. In the analysis of all 517 patients, there were no significant differences in the clinicopathological characteristics between the two treatment groups, with the exception of smoking status (P<0.001). The robotic group had a shorter operative time (OT; 209 vs. 228 min, P=0.004), fewer postoperative days (PODs) to first flatus (3 vs. 4 days, P=0.025), more PODs to removal of the drainage and nasogastric tubes (12 vs. 9 days, P=0.001; 6 vs. 4 days, P=0.001, respectively), and more postoperative complications (21.3 vs. 9.2%, P=0.003). Comparison of these short‑term outcomes of robotic and 3D‑HD laparoscopic gastrectomy performed by LC (144 patients) revealed that only the number of retrieved lymph nodes (27 in the robotic group vs. 33 in the 3D‑HD group; P=0.038) and PODs to removal of the nasogastric tube (5 days in the robotic group vs. 3 days in the 3D‑HD group; P<0.001) were significantly different. The OT stabilized after around 21 robotic gastrectomy procedures and 19 3D‑HD laparoscopic gastrectomy procedures. The cost‑effectiveness analysis revealed that robotic gastrectomy had a significantly higher total cost than 3D‑HD laparoscopic gastrectomy (124,907 vs. 94,395 RMB, P<0.001). With comparable surgical outcomes, lower financial cost and higher surgeons' acceptance, 3D‑HD laparoscopic gastrectomy is highly recommended as a minimally invasive surgical method for patients with GC prior to the popularization of robotic surgery.