Surgical outcomes and learning curve analysis of robotic gastrectomy for gastric cancer: multidimensional analysis in a comparison with 3D laparoscopic gastrectomy.

162 Background: There is a lack of supporting evidence regarding the safety, efficacy and surgeon acceptance of robotic versus three-dimensional (3D) laparoscopic surgery for patients with gastric cancer (GC). Methods: An ambispective cohort study was conducted. We compared short-term surgical outcomes including financial cost between robotic and 3D laparoscopic gastrectomy for all GC patients and the GC patients treated by Prof. Chen’s team. The Cumulative Sum (CUSUM) method was developed and used to analyze the learning curves of robotic and 3D laparoscopic gastrectomy performed by Prof. Chen. Results: From August 2011 to June 2017, a total of 517 patients were enrolled for treatment with either robotic (n=408 including n=73 performed by Prof. Chen) or 3D laparoscopic (n=109 including n=71 performed by Prof. Chen) gastrectomy. There were no significant differences between the two operation methods regarding the clinical pathological characteristics, except for smoking habit (p < 0.001). In analysis of all the 517 patients, robotic group had shorter operative time (208 min vs 228 min, p=0.004), less time to first flatus (3 days vs 4 days, p=0.025), longer time to remove drainage and nasogastric tube (12 days vs 9 days, p=0.001, 6 days vs. 4 days, p=0.001, respectively), and more postoperative complications (21.3% vs. 9.2%, p=0.003). While we compared these short-term outcomes of robotic and 3D laparoscopic gastrectomy performed by Prof. Chen, only number of lymph node dissections (robotic 27 vs. 3D 33, p=0.038) and time to remove nasogastric tube (robotic 5 days vs. 3D 3 days, p < 0.001) were significantly different. CUSUM analysis showed that operative time reached a stable state after around 21 cases in robotic gastrectomy and 19 cases in 3D laparoscopic gastrectomy. The cost-effectiveness analysis showed that robotic gastrectomy had significantly higher total cost than 3D laparoscopic gastrectomy (robotic = RMB 124907 vs. 3D-laparoscopic = RMB 94395; p < 0.001). Conclusions: With comparable surgical outcomes, higher surgeon acceptance and less financial cost, 3D laparoscope is a highly recommended minimal invasive surgical method for GC patients.

Clinical outcomes of three-dimensional versus two-dimensional laparoscopic surgery for gastric cancer: A single center, prospective, randomized trial—An interim report.

53 Background: Laparoscopic surgery is more challenging compared with open surgery, in part because surgeons must operate in three-dimensional (3D) space through a two-dimensional (2D) projection on a monitor, which results in loss of depth perception. To counter this problem, 3D imaging for laparoscopic was developed. However, there is limited evidence regarding its efficacy and safety. We therefore conducted a phase III, single center, prospective, randomized study to validate the efficacy and safety of 3D laparoscopic gastrectomy for gastric cancer compared with 2D laparoscopic surgery. Methods: The eligible criteria were pathologically-proven adenocarcinoma, 18 to 75 years of age, no history of other malignant tumor, chemotherapy, or radiotherapy, and clinical stage T1-4aN0-3M0 with R0 resection. The primary end point was to determine whether there is a difference in operation time between the two groups. The morbidity and mortality were compared to evaluate the safety of this trial. Results: A total of 196 patients were randomized (97 cases in 3D Group; 99 cases in 2D Group) between January 1, 2015 and August 31, 2015. There were no significant differences between the two groups in clinicopathological characteristics. The mean number of retrieved lymph nodes was similar in the 3D and 2D groups (35.6±14.1 vs. 36.1±13.5 per case). The operation time was similar in 3D and 2D groups (183.6±34.1 vs. 180.0±37.2 min). The blood loss in 3D Group was 59.6±45.6 ml, which was less than that in 2D Group (69.9±62.4 ml) without statistically different. There were no significant differences in times to resumption of activities, first flatus, resumption of soft diet, and post-operative stay between the two groups (P > 0.05, respectively). The morbidity of the 3D and 2D groups were 21.6% (21/97) and 17.1% (17/99), respectively (P = 0.428). There was no patient died during the postoperative stay in both groups. Conclusions: 3D laparoscopic gastrectomy is a safe and feasible procedure for gastric cancer. However, compared with 2D group, there was no so much benefit from 3D laparoscopic gastrectomy for gastric cancer. Clinical trial information: NCT02327481.