Robot-assisted versus conventional laparoscopic operation in anus-preserving rectal cancer: a meta-analysis

OBJECTIVE The aim of this meta-analysis is to provide recommendations for clinical practice and prevention of postoperative complications, such as circumferential resection margin (CRM) involvement, and compare the amount of intraoperative bleeding, safety, operative time, recovery, outcomes, and clinical significance of robot-assisted and conventional laparoscopic procedures in anus-preserving rectal cancer. METHODS A literature search (PubMed) was performed to identify biomedical research papers and abstracts of studies comparing robot-assisted and conventional laparoscopic procedures. We attempted to obtain the full-text link for papers published between 2000 and 2016, and hand-searched references for relevant literature. RevMan 5.3 software was used for the meta-analysis. RESULTS Nine papers (949 patients) were eligible for inclusion; there were 473 patients (49.8%) in the robotic group and 476 patients (50.2%) in the laparoscopic group. According to the data provided in the literature, seven indicators were used to complete the evaluation. The results of the meta-analysis suggested that robot-assisted procedure was associated with lower intraoperative blood loss (mean difference [MD] -41.15; 95% confidence interval [CI] -77.51, -4.79; P=0.03), lower open conversion rate (risk difference [RD] -0.05; 95% CI -0.09, -0.01; P=0.02), lower hospital stay (MD -1.07; 95% CI -1.80, -0.33; P=0.005), lower overall complication rate (odds ratio 0.58; 95% CI 0.41, 0.83; P=0.003), and longer operative time (MD 33.73; 95% CI 8.48, 58.99; P=0.009) compared with conventional laparoscopy. There were no differences in the rate of CRM involvement (RD -0.02; 95% CI -0.05, 0.01; P=0.23) and days to return of bowel function (MD -0.03; 95% CI -0.40, 0.34; P=0.89). CONCLUSION The Da Vinci robot was superior to laparoscopy with respect to blood loss, open conversion, hospital stay, and postoperative complications during anus-preserving rectal cancer procedures; however, conventional laparoscopy had an advantage regarding operative time. The remaining indicators (CRMs and recovery from intestinal peristalsis) did not differ.