The safety assessment of robotic versus laparoscopic gastrectomy for gastric cancer using a propensity score matching method.

Abstract

55 Background: We have previously reported the safety of robotic gastrectomy (RG) for clinical Stage IA or IB gastric cancer in single arm phase II studies. To date, a number of retrospective case control studies comparing RG and laparoscopic gastrectomy (LG) have been performed. However, since randomized controlled trials have never been conducted, no definitive conclusion demonstrating benefits of RG over LG has been demonstrated. In this study, we aimed to evaluate the safety of RG compared to LG using propensity score matching (PSM) methods. Methods: We retrospectively reviewed 766 consecutive patients who underwent either RG (n = 231) or LG (n = 535) for gastric cancer between January 2012 and December 2017. A 1:1 PSM was performed with the matched variables of age, sex, body mass index, performance status, clinical Stage, type of gastrectomy, and extent of lymphadenectomy. We compared short-term outcomes between the patients who underwent RG (RG group) and LG (LG group). Results: After PSM analysis, 231 patients were included in the RG group and 230 in the LG group. Intraoperative blood loss was similar between the groups. Operation time was significantly longer in the RG group (326 min vs. 281 min, P < 0.001). Significantly more lymph nodes were retrieved in the RG group (42 vs. 38.5, P = 0.031). Serum CRP level were significantly lower in the RG group in postoperative day 3 (9.0 mg/dL vs. 9.8 mg/dL, P = 0.049) and 6 (3.1 mg/dL vs. 3.7 mg/dL, P = 0.034), and drain amylase level in postoperative day 3 was also significantly lower in the RG group (612 U/L vs. 856 U/L, P < 0.001). Overall postoperative complication (Clavien–Dindo classification grade IIIA or greater) was similar between the groups (RG: 3.9% vs. LG: 5.6%, P = 0.656). However, pancreatic fistula tended to be less frequent in the RG group than in the LG group (0.4% vs. 2.2%, P = 0.122), although it did not reach statistically significant difference. Conclusions: Although RG takes longer operation time, it appears to be less invasive than LG with the possibility of decreased postoperative complications. To validate the results, randomized controlled trial should be performed.