An Observational Study for Gastric Cancer in Carriers of High Risk Helicobacter Pylori

This study is following people who carry a high-risk strain of Helicobacter pylori — a common stomach bacteria — to monitor whether they develop stomach cancer over time. H. pylori infection is the leading cause of stomach cancer worldwide, and certain strains are more dangerous than others. Researchers want to understand the natural progression from H. pylori infection to cancer, and identify who is at highest risk so that prevention strategies can be improved. **You may be eligible if...** - You are 40 years or older - You are willing to attend baseline and follow-up check-up appointments - You are able to provide informed consent **You may NOT be eligible if...** - You have already been diagnosed with stomach cancer or another digestive tract cancer - You have serious underlying health conditions (such as severe heart, lung, or kidney failure) that make follow-up unsafe - You are unable or unwilling to attend required follow-up visits - You have a condition that would make endoscopy (stomach camera examination) unsafe Talk to your doctor to see if this trial is right for you.