To establish prospective cohort of healthy population and corresponding serum sample bank in Sichuan province to provide platform for exploring early diagnosis and screening strategy of gastric cancer by a prospective cohort study.

H. pylori was one of the most important carcinogenic factor for gastric cancer and play a crucial role in inducing gastritis, atrophy and canceration. Chronic atrophic gastritis (CAG) was a common precancerous disease, people with CAG become high-risk population and need regular follow-up. However, study about occurrence risk prediction for gastric cancer when H. pylori infection concurrence with CAG was still spare. In especial, there was still no population screening program based on serology. The relative clinical epidemiology for providing evidence for China gastric cancer screening program was very rare.

This study aim to evaluate gastric cancer occurrence risk and diagnostic value of people combined with H. pylori infection and CAG by Serological methods in Sichuan province China. We also project to design optimized screening program suitable for people in sichuan province China.

Inclusion Criteria:

1. Inhabitant in Sichuan province in China (length of residence > 10 years);
2. Complete physical examination in our hospital, the outcomes was asymptomatic and cancer free healthy individuals;
3. Age between 20 and 70;
4. With normal cognitive and communication ability;
5. Without gastroscopy during recruitment, physical examination item including gastroscopy enrolled in prospective cohort study;
6. Wiling to accept 1-2 times routine physical examination in our hospital;
7. Agree to accept the follow-up of our project group;

Exclusion Criteria:

1. With history of malignant tumor;
2. Refuse to donate blood specimen;
3. With serious comorbidity and/or finite life (less than 5 years);
4. Request to retreat from this study;

In our study, the poplatiion was enrolled among health inhabitant in Sichuan province in China. People who underwent physical examination in our center who statisfy our indications will be introdeced to participate in our study. The informed consent will be endosed and the blood sample will be collected.

pending