Comparing treatment and outcomes in advanced esophageal, gastroesophageal junction, and gastric adenocarcinomas: a population-based study

Abstract

Background:Treatment of advanced or metastatic esophageal adenocarcinoma (EAC) follows the guidelines for gastroesophageal junction adenocarcinoma (GEJC) and gastric adenocarcinoma (GAC), but patients with EAC are often excluded from clinical studies of GEJC/GAC.Objectives:Here we describe treatment and survival of patients with advanced EAC, GEJC, and GAC to provide population-based evidence on distinctions and similarities between these populations.Design:Retrospective cohort study of patients with unresectable advanced (cT4b) or metastatic (cM1) EAC, GEJC, or GAC (2015–2020) were selected from the Netherlands Cancer Registry.Methods:Overall survival (OS) was assessed using Kaplan–Meier methods, log-rank tests, and multivariable Cox regression.Results:In all, 7391 patients were included (EAC: n = 3346, GEJC: n = 1246, and GAC: n = 2798). Patients with EAC were more often males and more often had ⩾2 metastatic locations. First-line systemic therapy was received by 42%, 47%, and 36% of patients with EAC, GEJC, and GAC, respectively. Median OS was 5.0, 5.1, and 4.0 months for all patients with EAC, GEJC, and GAC, respectively ( p < 0.001). Median OS from start of first-line therapy of patients with human epidermal growth factor receptor 2 (HER2)-negative adenocarcinomas was 7.6, 7.8, and 7.5 months ( p = 0.12) and of patients with HER2-positive carcinoma receiving first-line trastuzumab-containing therapy was 11.0, 13.3, and 9.5 months ( p = 0.37) in EAC, GEJC, and GAC, respectively. After multivariable adjustment, no difference in OS for patients with EAC, GEJC, and GAC was observed.Conclusion:Despite differences in clinical characteristics and treatment strategies, survival between patients with advanced EAC, GEJC, and GAC was similar. We advocate that EAC patients should not be excluded from clinical trials for patients with molecularly similar GEJC/GAC.