Robotic gastrectomy versus laparoscopic gastrectomy for gastric cancer: meta-analysis and trial sequential analysis of prospective observational studies

BackgroundTo evaluate short- and long-term outcomes of robotic gastrectomy (RG) in patients with gastric cancer to determine whether RG is an acceptable alternative to laparoscopic gastrectomy (LG).MethodsPubMed, Embase, the Cochrane Library, and Chinese Biomedical Database were searched for prospective observational studies (POSs) comparing RG with LG for gastric cancer until October 2017. We compared short-term and long-term outcomes using systematic review with meta-analysis and trial sequential analysis (TSA).ResultsSixteen POSs including 4576 patients were included in the meta-analyses. Compared with LG, RG had longer operative time (MD 57.98min, P<0.00001), lesser blood loss (MD -23.71ml, P=0.005), and shorter time to first post-operative flatulence (MD -0.14 days, P=0.03). No significant difference was found in terms of the number of harvested lymph nodes, complications, reoperation, mortality, open conversion, proximal resection margin, and distal resection margin. The meta-analyses of complications, overall survival, and disease-free survival did not yield any sign of statistically significant difference between the two treatments, and the cumulative Z-curve crossed neither the traditional boundary nor the trial sequential monitoring boundary, suggesting the lack of firm evidence. TSA demonstrated that the cumulative Z-curve crossed either the traditional boundary or the trial sequential monitoring boundary on blood loss and operative time.ConclusionsThe present study demonstrates that RG is as acceptable as LG in terms of short- and long-term outcomes. The TSA demonstrated that further studies are not needed to evaluate the operative time and blood loss differences between these techniques.