摘要Objective:The laparoscopic approach for locally advanced gastric cancer has recently been adopted based on the results of several randomized controlled trials(RCTs).However,findings from RCTs have not been examined at the national level.This study aimed to investigate the external validity of the Korean Laparoscopic Gastrointestinal Surgery Study-02(KLASS-02)trial involving 13 tertiary hospitals,using data from the Korean Gastric Cancer Association(KGCA)-led nationwide survey involving 68 tertiary or general hospitals.Methods:Data on patients who underwent laparoscopic or open distal gastrectomy for pathological stageⅠB-ⅢC gastric cancer under the same conditions were collected from the KLASS-02 trial and the KGCA nationwide survey datasets.Surgical outcomes were assessed for each dataset and multivariable analyses were performed to examine the effect of the laparoscopic approach on surgical outcomes.Results:The laparoscopic group had a lower overall complication rate than the open group in both KLASS-02 and KGCA datasets(16.1％vs.23.5％for the KLASS-02 and 12.6％vs.19.6％for the KGCA).Moreover,the laparoscopic group had fewer wound problems,and fewer grade Ⅱ,Ⅲa,and Ⅳ complications than the open group in the KGCA data(0.8％vs.3.4％,5.8％vs.10.4％,2.3％vs.3.7％,and 0.5％vs.1.4％,respectively),which were not observed in the KLASS-02 data.Multivariable analyses revealed that the laparoscopic approach was not associated with overall complications,but reduced wound problems and more harvested lymph nodes in the KGCA survey data(adjusted odds ratios,0.19 for wound problems,adjusted β coefficient 4.39 for number of harvested lymph nodes),which were not shown in the KLASS-02 data.Conclusions:The safety and feasibility of the laparoscopic approach for locally advanced gastric cancer were validated at a national level.The laparoscopic approach for locally advanced gastric cancer can be implemented in the Republic of Korea.