Efficacy analysis of Da Vinci robotic and laparoscopic distal gastrectomy for gastric cancer using propensity score matching

Abstract

Objective To investigate the clinical efficacy of Da Vinci robotic and laparoscopic distal gastrectomy for gastric cancer. Methods The propensity score matching and retrospective cohort study was conducted. The clinicopathological data of 171 patients with gastric cancer who were admitted to the First Affiliated Hospital of Nanchang University from January 2015 to October 2016 were collected. There were 110 males and 61 females, aged from 38 to 81 years, with a median age of 57 years. Of 171 patients, 70 undergoing Da Vinci robotic distal gastrectomy for gastric cancer and 101 undergoing laparoscopic distal gastrectomy were allocated into the robotic group and laparoscopic group, respectively. Observation indicators: (1) the propensity score matching conditions and comparison of general data between the two groups after the propensity score matching; (2) intraoperative and postoperative situations; (3) situations of pathological examination; (4) follow-up. Patients were followed up by outpatient examination and telephone interview to detect severe complications and survival after discharge up to October 2018. The overall survival time was from the operation data to end of follow-up or time of death. The propensity score matching was used to perform 1∶1 matching by Empower Stats. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was done using the t test. Measurement data with skewed distribution were represented as M (range), and comparison between groups was done using the Mann-Whitney U test. Count data were represented as absolute number, and comparison between groups was analyzed using the chi-square test and comparison of ordinal data between groups was analyzed using the Mann-Whitney U test. The survival rate and curve were respectively calculated and drawn by the Kaplan-Meier method, and Log-rank test was used for survival analysis. Results (1) The propensity score matching conditions and comparison of general data between the two groups after the propensity score matching: 124 of 171 patients had successful matching, including 62 in each group. The body mass index (BMI) and tumor diameter before matching were (24.2±2.4)kg/m2 and (50±13)mm in the robotic group, (25.1±2.1)kg/m2 and (45±14)mm in the laparoscopic group, showing statistically significant differences between the two groups (t=-2.676, 2.045, P 0.05). (2) Intraoperative and postoperative situations: the total operation time, volume of intraoperative blood loss, level of C-reactive protein at day 1 postoperatively, level of C-reactive protein at day 3 postoperatively, volume of totally abdominal drainage were (147±13)minutes, (115±12)mL, (52.2±7.2)mg/L, (33.7±11.9)mg/L, 353.5 mL (range, 267.0-1 350.0 mL) in the robotic group, and (140±12)minutes, (131±12)mL, (58.2±7.4)mg/L, (41.1±16.9)mg/L, 397.0 mL (range, 255.0-1 600.0 mL) in the laparoscopic group, respectively, showing statistically significant differences in the above indexes between the two groups (t=3.163, -7.814, -4.631, -2.840, Z=-4.351, P 0.05). Conclusions Compared with laparoscopic surgery, Da Vinci robotic distal gastrectomy for gastric cancer has advantages in postoperative recovery and minimally invasion. There are similar 2-year overall survival rates in the two groups. Key words: Gastric neoplasms; Gastric cancer; Da Vinci robotic surgery system; Laparoscopy; Propensity score matching; Clinical efficacy