This study is a case-control study. Patients, according to the pathological results, will be consecutively enrolled and divided into gastric cancer group, gastric precancerous lesions group, and chronic gastritis group. The serum and gastric juice bile acid profiles, gastric microbial composition of each group patients will be detected.
To explore the associations among bile acid profile, bile acid-microbiota cross-talk and the development of gastric cancer, so as to better prevent the occurrence and development of gastric cancer