Establishment of subcutaneous transplantation tumor model and application in adjuvant chemotherapy of gastric cancer

INTERVENTION: test group:chemotherapy by the outcome of chemosensitivity assay;control group:chemotherapy (EOF, DC, XELOX, S‐1); CONDITION: gastric cancer PRIMARY OUTCOME: 3‐year disease‐free survival;Adverse Reactions; SECONDARY OUTCOME: 3‐year overall survival;5‐year overall survival; INCLUSION CRITERIA: A histologically proven diagnosis of gastric adenocarcinoma; radical resection of the tumor not more than 8 weeks before the date of random assignment with no evidence of residual disease as determined by staging exams; gastric cancer of stages IB, II, IIIA B, or IV (T4N2M0) according to the American Joint Committee on Cancer ‐ Cancer Staging 2010; Eastern Cooperative Oncology Group performance status (ECOGPS) less than 2; no previous malignancies other than superficial skin cancer or in situ cervical carcinoma; no previous treatments such as neoadjuvant chemotherapy or radiotherapy;and no evidence of abnormal hepatic, renal, or cardiac function. Written informed consent and approval by the local ethics committee was obtained for all patients in the study before random assignment. Surgical procedures were not standardized among participating centers. In the protocol, the minimum surgical recommendations included total or subtotal gastrectomy with negative resection