Proximal Gastrectomy versus Total Gastrectomy for Siewert Type II Adenocarcinoma of the Esophagogastric Junction: A Comprehensive Analysis of Data from the SEER Registry

Background. To determine the ideal surgical approach (total gastrectomy (TG) vs. proximal gastrectomy (PG)) for Siewert type II adenocarcinoma of the esophagogastric junction (AEG), we searched and analyzed the Surveillance, Epidemiology, and End Results (SEER) data. Methods. Patients with Siewert type II AEG treated by TG or PG were identified from the 2004-2014 SEER dataset. We obtained the patients' overall survival (OS) and cancer-specific survival (CSS) and stratified the patients by surgical approach. We performed a propensity score 1 : 1 matching (PSM) analysis and a univariate and multivariate Cox proportional hazards model. Results. A total of 2,217 patients with 6th AJCC stage IA-IIIB Siewert type II AEG was examined: 1,584 patients (71.4%) underwent PG, and 633 patients (28.6%) underwent TG. The follow-up time was 1-131 months. OS favored total gastrectomy before the PSM analysis (chi 2=3.952, p=0.047), but after this analysis, there was no significant difference between TG and PG (chi 2=2.227, p=0.136). The univariate and multivariate analyses identified age as an independent factor, and an X-tail analysis revealed 70 years as a cut-off point. The patients aged >= 70 years obtained a significant long-term OS benefit from PG compared to TG (chi 2=8.245, p=0.004), and those aged<70 years showed no difference between TG and PG (chi 2=0.167, p=0.682). Conclusions. PG showed an equivalent survival benefit to TG in both the early and locally advanced stages of Siewert type II AEG. For elderly patients, PG is strongly recommended because of its clearer OS benefit compared to TG.