A Clinical Trial of Two Adjuvant Chemotherapy Regimens for Postoperative Gastric Cancer

Inclusion Criteria: * Have signed the informed consent and can comply with the visit and related procedures stipulated in the program * Age ≥18 years old and ≤75 years old * D2 radical resection was performed within 21-60 days before the beginning of the first cycle of chemotherapy in this clinical study * Preoperative neoadjuvant chemotherapy was not performed and Gastric and gastroesophageal junction adenocarcinoma (including signed-ring cell carcinoma, mucinous adenocarcinoma, and hepatoid adenocarcinoma) at stage IIIB and IIIC were confirmed by postoperative pathological staging. Note: the presence of distant metastases should be confirmed by a CT or MRI scan.ECT should be performed if bone metastases are suspected.If peritoneal metastases are suspected, laparoscopy should be performed * Postoperative ECOG score was 0 or 1 * Leukocyte ≥ 4×109/L, platelet ≥ 100×109/L without blood transfusion, neutrophil absolute value (ANC) ≥ 1.5×109/L without granulocyte stimulating factor treatment, and hemoglobin ≥ 90 g/L * Bilirubin ≤ 1.5 times of the upper limit of normal value, glutamic oxalacetic transaminase and glutamic-pyruvic transaminase ≤ 2.5 times of the upper limit of normal value * Serum creatinine ≤ 1.5 times the upper limit of normal value, or GFR\>45 ml/min * Serum albumin ≥ 25 g/L (2.5g /dL) * INR or PT ≤ 1.5 times ULN * Hepatitis b surface antigen positive patients need to be tested for hepatitis b DNA virus quantitative detection, only \< the upper limit of the normal detection value can be included in the group, and should long-term use of anti-hepatitis b drugs * Tumor specimens can be provided for consultation (if the patient's surgical specimen comes from another hospital), protein and gene testing Exclusion Criteria: * Postoperative wound healing is poor and chemotherapy is not appropriate to start * Recurrent patients or suspected peritoneal metastases after radical surgery * Known DPD enzyme deficiency * Allergy to, or history of severe allergy to, or contraindication to any of the experimental drugs or its excipients * Patients who are expected to require major surgery during the study period * Congenital pulmonary fibrosis, drug-induced pneumonia, organized pneumonia, or CT-confirmed active pneumonia * Tested positive for HIV * Active hepatitis b or c * Only liquid diet was allowed after the operation, with BMI \<18kg/m2 * Uncontrolled pain * A history of antitumor drug therapy other than radical surgery * Severe infection in the active stage or with poor clinical control * Use of hormones is contraindicated * Severe cardiovascular disease, myocardial infection or cerebrovascular accident, arrhythmia, unstable angina pectoris within 3 months before the trial * Uncontrollable increase in blood pressure or blood sugar * A history of other malignancies within 5 years, except for carcinoma in situ of the cervix, non-melanoma skin cancer, or stage I uterine cancer * Distant metastases are known * Peripheral neuropathy ≥ NCI CTCAE grade 2 * Serum albumin \< 2.5 g/dL * Chronic enteritis * Any other disease for which there is evidence of a need to limit the use of experimental drugs * Participate in additional trials up to 30 days before the trial or plan to participate in additional trials while the trial is ongoing * Receive other experimental drugs up to 28 days before the start of the trial * Women who are pregnant or nursing, or who plan to become pregnant within five months of the end of treatment. Women of childbearing age should receive a blood/urine pregnancy test 7 days before the start of the trial * Clinically significant active bleeding * Patients who have trouble swallowing tablets * Previous allogeneic bone marrow transplant or organ transplant