In this study, the composition and level of serum bile acids in patients with gastric cancer and non-gastric cancer were analyzed by detecting the serum bile acid profile, so as to develop new serological diagnostic methods for early diagnosis and treatment of gastric cancer.

Inclusion Criteria:

1. Age between 18-70, both gender;
2. The gastric cancer group was early gastric cancer or advanced gastric cancer diagnosed by endoscopic examination and pathological biopsy. The non-gastric cancer group included patients without gastric lesions, superficial gastritis, chronic atrophic gastritis, intestinal metaplasia or dysplasia diagnosed by gastroscopy or pathological biopsy;
3. Informed consent was obtained.

Exclusion Criteria:

1. The patients have diseases that affect bile acid metabolism, such as liver cirrhosis, gallstones or inflammatory bowel disease, Behcet's disease, etc;
2. Due to other diseases, the patient took drugs affecting bile acid metabolism, such as cholestyramine, anti-inflammatory Lidan tablets, Danshu capsules, ursodeoxycholic acid, obticholic acid, Schisandrin B, tanshinone ⅡA, Yinzhihuang, etc;
3. Pregnant women;
4. Primary tumors of other systems were diagnosed;
5. Those with poor physiopathological conditions, such as chronic kidney disease requiring long-term dialysis;
6. Patients with mental illness;
7. Patients who have received radiotherapy or surgery previously;
8. Those with poor adherence or difficult to follow up.

Patients attending Xijing Hospital and Patients included in the biospecimen bank