[Real-world data analysis of 3012 patients undergoing laparoscopic radical gastrectomy in a single center over the...

Objective: To Summarize the safety, clinical outcome and technical evolution of laparoscopic gastric cancer surgery. Methods: A retrospective cohort study was carried out. Clinical data of 3012 patients who underwent laparoscopic radical gastrectomy for gastric cancer from January 2010 to March 2022 at Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University were retrospectively collected and analyzed. Case inclusion criteria were gastric malignancies confirmed by pathology, without distant metastasis by examination before operation and exploration during operation, patients undergoing laparoscopic radical gastrectomy, intact function of important organs and with complete data. Exclusion criteria were patients who underwent emergency gastric cancer resection due to gastric bleeding, perforation or obstruction, etc., tumor found to invade adjacent organs such as pancreas or transverse colon during the operation, conversion to open surgery during the operation, those who had other malignant tumors (except thyroid cancer) within 5 years, and those had severe cardiopulmonary, liver, or kidney insufficiency before surgery. Outcomes included: (1) baseline information of patients; (2) trend of the quantity of laparoscopic radical gastrectomy year by year; (3) evolution of the mode of digestive tract reconstruction; (4) periopertive outcome short-term complication was defined as complication occurring within 30 days after operation and classified accordiny to the clavien-Dindo criteria; and (5) 5-year overall survival. SPSS software was used for statistical analysis. Continuous variables that obeyed the normal distribution were expressed in the form of Mean±SD. Days of hospital stay that did not follow a normal distribution were expressed as median (Q₁,Q₃), and the Mann-Whiney U test was used for comparison. Discrete variables were expressed as cases (%), and chi-square test or rank sum test was used for comparison between groups. Linear regression analysis was used to analyze the relationship between the amount of surgery and the year of surgery. Kaplan-Meier method and log-rank test were used for survival analysis. Two-tailed P<0.05 was considered as statistically significant. Results: Among the 3012 cases, 2114 were male and 898 were female. The patients' average age at surgery was (61.1±10.7) years old. According to the number of cumulative cases, the patients were divided into three groups: early, intermediate and late, with 1004 patients in each group. The early group consisted of patients undergoing operation from January 2010 to October 2018, the intermediate group consisted of patients undergoing operation from October 2018 to January 2021, and the late group consisted of patients undergoing operation from January 2021 to March 2022. (1) General information: There were 691 (68.8%), 699 (69.6%) and 724 (72.1%) male patients in early, intermediate and late groups respectively; the average age increased from 56.6 years in 2010 to 62.8 years in March 2022. As for the tumor stage T1, T2, T3, T4, there were 49.0%, 14.4%, 23.9% and 12.6% in the early group; 47.5%, 12.9%, 26.9% and 12.6% in the intermediate group; 39.7%, 14.6%, 30.0%, and 15.6% in the late group, respectively. Patients with N0, N1, N2, N3a, N3b stage were 56.8%, 13.7%, 13.4%, 11.0%, and 5.0% in the early group; 55.7%, 12.9%, 12.8%, 11.6%, and 6.9% in the intermediate group; 51.0%, 16.1%, 12.8%, 12.5%, and 7.5% in the late group, respectively. (2) Year-by-year change in the number of gastric cancer operations: From 19 cases per year in 2010 to 786 per year in 2021, the annual number of gastric cancer operations was proportional to the year of operation (y=47.505x, R²=0.67). The proportion of patients with stage I disease showed a fluctuating downward trend over time, while the proportion of patients with stage III disease increased slightly, accounting for 34% until March 2022. (3) Evolution of digestive tract reconstruction methods: Except in 2010, the digestive tract reconstruction method of distal gastrectomy focused on Billroth-II+Braun anastomosis among patients undergoing laparoscopic gastric cancer surgery in other years, whose proportion had gradually increased from less than 20% in 2016 to about 70% after 2021; the gastrointestinal reconstruction methods after total gastrectomy had gradually increased in π anastomosis and overlap anastomosis since 2016, of which π anastomosis reached about 65% in 2019, and overlap anastomosis reached almost 30% in 2020; the anastomosis methods after proximal gastrectomy had been mainly double-channel anastomosis (54%) and esophagogastric anastomosis (30%) since 2016, and double-channel anastomosis accounted for up to 70% in 2019. (4) Operation time: The operation time of early, intermediate and late group was (193.3±49.8) min, (186.9±44.3) min and (206.7±51.4) min respectively. Intermediate group was significantly shorter than early group (t=3.005, P=0.003), while late group was significantly longer than early group (t=5.875, P<0.001) and intermediate group (t=9.180, P<0.001). (5) Postoperative hospital stay: The median length of hospital stay for gastric cancer patients in early, intermediate and late groups was 9 (8, 11) d, 8 (7, 10) d, and 8 (7.5, 10) d respectively. The postoperative hospital stay of intermediate group and late group was significantly shorter than that of early group (Z=-12.467, Z=-5.981, both P<0.001), but there was no significant difference between intermediate group and late group (Z=0.415,P=0.678). (6) Postoperative complication: The morbidity of short-term complication in early, intermediate and late group was 20.4% (205/1004), 16.2% (163/1004), and 16.2% (162/1004) respectively, and above morbidity of intermediate group and late group was significantly lower than that of early group (χ²=5.869, P=0.015; χ²=6.165, P=0.013), while there was no significant difference between intermediate group and late group (χ²=0.004,P=0.952). The morbidity of short-term complication of grade IIIor higher was 8.0% (80/1004), 7.6% (76/1004), and 4.9% (49/1004) in early, intermediate and late group respectively, and above morbidity of late group was significantly lower than that of early and intermediate group (χ²=7.965, P=0.005; χ²=6.219,P=0.013), while there was no significant difference between intermediate group and early group (χ²=0.111,P=0.739). (7) Survival analysis: The follow-up deadline for survival data was December 31, 2021, and the median follow-up time was 29.5 months. The overall 5-year survival rate of all the patients was 74.7%. The 5-year survival rates of stage I, II and III patients were 92.0%, 77.2%, and 40.3% respectively and 5-year survival rates of patients with stage IA, IB, IIA, IIB, IIIA, IIIB and IIIC were 93.2%, 87.8%, 81.1%, 72.7%, 46.2%, 37.1%, and 34.0% respectively. Conclusions: The number of laparoscopic gastric cancer operation in our center is increasing year by year. With the maturity of laparoscopic technology, the morbidity of complication in laparoscopic gastric cancer surgery is decreasing.