Enriched-CRT 2017: Advanced Gastric Cancer With LN+ and LVI+, Chemotherapy vs. Chemoradiotherapy

Inclusion Criteria: * 1\. Aged 18-75 years； * 2\. Primary lesion is pathologically diagnosed as gastric adenocarcinoma (including Esophagogastric Junction adenocarcinoma), such as papillary adenocarcinoma, tubular adenocarcinoma, mucinous adenocarcinoma, poorly cohesive carcinoma (including signet ring cell carcinoma and other variants), and mixed adenocarcinoma; * 3\. Received radical resection: R0 gastrectomy with D1/D2 lymphadenectomy (at least 15 lymph nodes were examined); * 4\. Pathological stage pT2-4aN1-3M0 (According to American Joint Committee on Cancer (AJCC)-7th Tumor-Node-Metastasis (TNM) staging system), and with lymphovascular invasion, (LVI+); * 5\. No evidence of distant metastases was observed by perioperative imaging; * 6\. Postoperative performance status (ECOG, Eastern Cooperative Oncology Group) of 0-2; * 7\. No prior treatment of chemotherapy, radiotherapy, targeted therapy, immunotherapy, etc.; * 8\. Adequate hematological function: Hemoglobin (Hb) ≥100g/L, Neutrophil count (ANC) ≥1.5×109/L, Platelet count (PLC) ≥100×109/L; * 9\. Adequate liver function: ALT、AST ≤2.5x upper limit of normal (ULN), Alkaline phosphatase (ALP) ≤2.5x ULN, Serum total bilirubin (TBIL) \<1.5x ULN, Serum albumin(Alb) ≥30g/L; * 10\. Adequate renal function: Serum creatinine ≤1.5mg/dl; * 11\. Be able of oral feeding; * 12\. Written informed consent. Exclusion Criteria: * 1\. Synchronous or metachronous (within 5 years) malignancies; * 2\. Body temperature ≥ 38℃ or infectious disease with a systemic therapy indicated; * 3\. Severe neurological or mental disease, including seizures or dementia, which may interfere compliance and sign of consent inform. * 4\. Severe heart disease, including unstable angina pectoris, New York Heart Association (NYHA) class II or more advanced heart failure, severe arrhythmia despite medicinal treatment, or history of myocardial infarction within 12 months; * 5\. Severe respiratory disease; * 6\. Moderate or severe renal dysfunction: Creatinine clearance rate (CCR) ≤50 ml/min, or Serum creatinine \>ULN ; * 7\. Upper gastrointestinal tract obstruction, physiological dysfunction, or malabsorption syndrome, which affect the absorption of oral drugs; * 8\. Peripheral nervous disease (NCI CTC version\> 1.0 grade), except for patients with ony disappeared deep tendinous reflect (DTR); * 9\. Women during pregnancy or breast-feeding; * 10\. Fertile women with a positive pregnancy test, or no pregnancy test; postmenopausal within 12 months; * 11\. Fertile men or women who refuse to use contraception during the study period; * 12\. Patients are participating or have participated in another clinical trial (within 6 months); * 13\. Continuous systemic steroid therapy within 1 month (except for topical use), or received organ transplantation that needs immunosuppressive agent; * 14\. Dihydropyrimidine dehydrogenase (DPD) deficiency; * 15\. Allergy to platinum compound, or any component of drugs used in the study.