This study is a multicenter, prospective cohort study, which are planned to enroll at least 600 patients who diagnosed the primary gastric cancer (GC); around 50 patients with premalignant gastric lesions (PGLs) and early gastric neoplasias (EGC) treated by endoscopy resection; and no less than 600 healthy normal cohort participants, for more than 18 months in the Spanish population. All participants who enrolled in this registry will be questioned by the life habits survey; and clinical data and biological samples of these participants were analyzed in order to look for new diagnostic tools. The aim of this study is to evaluate clinical, endoscopic and molecular approaches to identify individuals with high-risk of GC. Thus, it would be allow the adoption of preventive measures to reduce mortality through early detection and/or the reduction of its incidence.