Costs of Opportunistic Upper Gastrointestinal Endoscopy and the Economic Burden of Gastric Cancer Management

Inclusion Criteria: Cohort A: * Eligible participants were adults aged 50 to 75 years or older who had been referred for colonoscopy as part of the national colorectal cancer screening programme, following a positive FIT. To be included, individuals also needed to provide informed consent and agree to undergo an EGD endoscopy for the screening of potential upper gastrointestinal precancerous conditions or lesions. Cohort B: * Patients with gastric adenocarcinoma, diagnosed and treated at Unidade Local de Saúde do Alto Alentejo between 2015 and 2025. Exclusion Criteria: Cohort A: * Exclusion criteria included a prior diagnosis of gastric cancer, as well as any condition that would prevent the safe performance of the EGD or the collection of gastric mucosal biopsies. Previous EGD was not listed as an exclusion criterion. Cohort B: * Other types of gastric tumors. * Gastric involvement from metastatic disease of another primary tumor.