This is a multi-center, non-randomized, 3-cohort, phase II trial, evaluating a triplet combination of docetaxel, oxaliplatin and fluorouracil for gastric cancer with peritoneal carcinomatosis and inoperable malignant bowel obstruction.

The primary study hypothesis is that the regimen will provide a clinically meaningful bowel obstruction clearance. This trial has 3 paralleled cohorts with the same experimental regimen: Cohort A (first-line therapy) will include 35 participants who have not received any palliative chemotherapy; Cohort B (second-line therapy) will include 22 participants who progress after the first-line therapy; Cohort C (third- or later-line therapy) plans to include 22 cases who have received two or more prior therapies for their metastatic disease.

Inclusion Criteria:

• 18-75 years of age;
• ECOG PS ≤3;
• pathologically diagnosed gastric or gastroesophageal junctional adenocarcinoma;
• peritoneal carcinomatosis established by imaging data or pathological evidence;
• MBO below the Treitz ligament based on clinical grounds or radiological findings;
• considered as inoperable MBO by two independent surgical consultants;
• Hb≥60g/L, WBC ≥4×10E9/L, ANC≥2×10E9/L，PLT≥100×10E9/L;
• Cr≤ Upper Normal Limit(UNL);
• Tbil≤1.5 UNL,AST≤1.5 UNL, ALT≤1.5 UNL, ALP≤1.5 UNL;
• Written informed consent form paticipants.

Exclusion Criteria:

• treated by a combination regimen containing all the study drugs;
• allergy to any of the study drugs;
• HER-2 amplification or overexpression, mismatch repair protein expression deletion (dMMR), or genetic testing suggestive of high microsatellite instability (MSI-H);
• strangulated intestinal obstruction;
• active gastrointestinal bleeding;
• uncontrolled active infection;
• unstable heart diseases with severe ECG abnormalities or affect clinical treatment (such as cardiac insufficiency, myocardial infarction, angina);
• severe lung diseases (such as interstitial pneumonia, pulmonary fibrosis, severe emphysema, etc);
• mental disorders that affect clinical treatment or central nervous system diseases;
• concomitant cerebral parenchymal or meningeal metastasis;
• HIV infection or untreated active hepatitis;
• bowel surgery or stenting required due to obstruction;
• pregnant or lactating women;
• other conditions that are not suitable for participation in the study.