Nonintervention Study on Peritoneal Metastasis of Stage IV Gastric Cancer

Inclusion Criteria: * 18 ≤ age * Patients with histologically confirmed gastric cancer or gastroesophageal junction adenocarcinoma, stage IV with peritoneal metastasis * Didn't received any prior systemic chemotherapy * Signed informed consent Exclusion Criteria: * History of hypersensitivity to fluoropyrimidines, Tegafur，Gimeracil and Oteracil Potassium Capsules , capecitabine, oxaliplatin or the ingredients of this product * Pregnancy or lactation women, * Inadequate hematopoietic function： WBC≦3,500/mm3; ANC≦1,500/mm3; Platelet≦80,000/mm3 * Inadequate organ function which is defined as below: Total bilirubin \>2 pper limit of normal range (ULN); ALT / AST \> 2.5 upper limit of normal range (ULN); serum creatinine \> 1.5 mg/dL, and Ccr \> 60 ml/min (estimated by Cockcroft-Gault formulation); * Symptomatic peripheral neuropathy * Receiving a concomitant treatment with other fluoropyrimidines * Fluoropyrimidines (DPD) congenital absence * Other Situations which physicians suggesting are inadaptable for enrollment