Long-term oncologic outcomes of robotic gastrectomy for gastric cancer compared with laparoscopic gastrectomy

Background Initial experiences with robotic gastrectomy (RG) for gastric cancer have demonstrated favorable short-term outcomes, suggesting that RG is an effective alternative to laparoscopic gastrectomy (LG). However, data on long-term survival and recurrence after RG for gastric cancer have yet to be reported. The objective of this study was to assess long-term outcomes after RG compared with LG. Methods We retrospectively evaluated 313 and 524 patients who underwent RG or LG, respectively, for gastric cancer between July 2005 and December 2009. We compared long-term outcomes using the entire and a propensity-score matched cohort. Results The entire cohort analysis revealed no statistically significant differences in 5-year overall survival(OS) or relapse-free survival(RFS) ( p = 0.4112 and p = 0.8733, respectively): 93.3% [95% confidence interval (CI) 89.9–95.6] and 90.7% (95% CI, 86.9–93.5) after RG and 91.6% (95% CI 88.9–93.7) and 90.5% (95% CI 87.6–92.7) after LG, respectively; hazard ratios for death and recurrence in the robotic group were 0.828 (95% CI, 0.528–1.299; p = 0.4119) and 0.968 (95% CI, 0.649–1.445; p = 0.8741), respectively. The propensity-matched cohort analysis demonstrated no statistically significant differences for 5-year OS or RFS ( p = 0.5207 and p = 0.2293, respectively): 93.2% and 90.7% after RG and 94.2% and 92.6% after LG, respectively; hazard ratios for death and recurrence in the robotic group were 1.194 (95% CI, 0.695–2.062; p = 0.5214) and 1.343 (95% CI, 0.830–2.192; p = 0.2321), respectively. Conclusion The potential technical superiority of robotic system over laparoscopy did not improve oncological outcomes after gastrectomy. Long-term oncological outcomes were not different between RG and LG. Nevertheless, robotic applications in minimally invasive gastric cancer surgery may be an oncologically safe alternative.