Prognostic factors of minimally invasive surgery for gastric cancer: Does robotic gastrectomy bring oncological benefit?

BACKGROUNDGastric cancer is the third leading cause of cancer-related death worldwide and surgical resection remains the sole curative treatment for gastric cancer. Minimally invasive gastrectomy including laparoscopic and robotic approaches has been increasingly used in a few decades. Thus far, only a few reports have investigated the oncological outcomes following minimally invasive gastrectomy.AIMTo determine the 5-year survival following minimally invasive gastrectomy for gastric cancer and identify prognostic predictors.METHODSThis retrospective cohort study identified 939 patients who underwent gastrectomy for gastric cancer during the study period. After excluding 125 patients with non-curative surgery (n = 77), other synchronous cancer (n = 2), remnant gastric cancer (n = 25), insufficient physical function (n = 13), and open gastrectomy (n = 8), a total of 814 consecutive patients with primary gastric cancer who underwent minimally invasive R0 gastrectomy at our institution between 2009 and 2014 were retrospectively examined. Accordingly, 5-year overall and recurrence-free survival were analyzed using the Kaplan-Meier method with the log-rank test and Cox regression analyses, while factors associated with survival were determined using multivariate analysis.RESULTSOur analysis showed that age > 65 years, American Society of Anesthesiologists (ASA) physical status 3, total or proximal gastrectomy, and pathological T4 and N positive status were independent predictors of both 5-year overall and recurrence-free survival. Accordingly, the included patients had a 5-year overall and recurrence-free survival of 80.3% and 78.2%, respectively. Among the 814 patients, 157 (19.3%) underwent robotic gastrectomy, while 308 (37.2%) were diagnosed with pathological stage II or III disease. Notably, our findings showed that robotic gastrectomy was an independent positive predictor for recurrence-free survival in patients with pathological stage II/III [hazard ratio: 0.56 (0.33-0.96), P = 0.035]. Comparison of recurrence-free survival between the robotic and laparoscopic approach using propensity score matching analysis verified that the robotic group had less morbidity (P = 0.005).CONCLUSIONAge, ASA status, gastrectomy type, and pathological T and N status were prognostic factors of minimally invasive gastrectomy, with the robot approach possibly improving long-term outcomes of advanced gastric cancer.