Efficacy and safety of chemotherapy in young patients with advanced gastroesophageal adenocarcinoma: data from the Spanish AGAMENON-SEOM registry

Background Gastroesophageal adenocarcinoma in young adults (GCYA) counts for 10–15% of diagnoses. Previous studies have mainly focused on surgical outcomes in patients with resectable tumors; however, systemic therapy for advanced GCYA remains under-evaluated. This study aims to assess the efficacy-related outcomes and safety of first-line chemotherapy (CT) in younger versus older patients with advanced gastroesophageal adenocarcinoma. Methods Patients with advanced gastroesophageal adenocarcinoma from the AGAMENON-SEOM registry treated with first-line polychemotherapy between January 2008 and October 2022 were included. We compared clinicopathological features, therapies received, efficacy-related outcomes, and toxicity between individuals aged