Long-Term Survival after Minimally Invasive Versus Open Gastrectomy for Gastric Adenocarcinoma: A Propensity Score-Matched Analysis of Patients in the United States and China

Background This study aimed to compare the long-term survival of patients undergoing minimally invasive gastrectomy and those undergoing open gastrectomy for gastric adenocarcinoma (GA) in the United States and China. Methods Data on patients with GA who underwent gastrectomy without neoadjuvant therapy were retrieved from prospectively maintained databases at Memorial Sloan Kettering Cancer Center (MSKCC) and Fujian Medical University Union Hospital (FMUUH). Using propensity score-matching (PSM), equally sized cohorts of patients with similar clinical and pathologic characteristics who underwent minimally invasive versus open gastrectomy were selected. The primary end point of the study was 5-year overall survival (OS). Results The study identified 479 patients who underwent gastrectomy at MSKCC between 2000 and 2012 and 2935 patients who underwent gastrectomy at FMUUH between 2006 and 2014. Of the total 3432 patients, 1355 underwent minimally invasive gastrectomy, and 2059 underwent open gastrectomy. All the patients had at least 5 years of potential follow-up evaluation. Before PSM, most patient characteristics differed significantly between the patients undergoing the two types of surgery. After PSM, each cohort included 889 matched patients, and the actual 5-year OS did not differ significantly between the two cohorts, with an OS rate of 54% after minimally invasive gastrectomy and 50.4% after open gastrectomy ( p = 0.205). Subgroup analysis confirmed that survival was similar between surgical cohorts among the patients for each stage of GA and for those undergoing distal versus total/proximal gastrectomy. In the multivariable analysis, surgical approach was not an independent prognostic factor. Conclusions After PSM of U.S. and Chinese patients with GA undergoing gastrectomy, long-term survival did not differ significantly between the patients undergoing minimally invasive gastrectomy and those undergoing open gastrectomy.