RecruitingProcedureRisk Assessment Evaluation for Identifying Participants at High Risk for Stomach CancerThis clinical trial evaluates the usefulness of various risk assessment tests, including Helicobacter pylori (H. pylori) breath testing, questionnaires, and endoscopies for identifying participants at high risk for stomach cancer. H. pylori is a bacteria that causes stomach inflammation and ulcers in the stomach. People with H. pylori infections may be more likely to develop cancer in the stomach. H. pylori breath testing can help identify the presence of H. pylori infection in a participant and help identify if the participant may be at a higher risk of developing stomach cancer. An endoscopy uses a thin, flexible lighted tube that is inserted inside the esophagus, stomach, and first part of the small intestine. This allows the doctor to see and look for abnormal areas that may need to be biopsied. Risk assessment including H. pylori evaluation, questionnaires, and endoscopies may help identify participants at high risk for stomach cancer and may be a useful screening tool for earlier stomach cancer diagnosis.