This is a prospective pilot study to evaluate the safety and feasibility of neoadjuvant transcatheter infusion and embolism (TACiE) in patients with locally advanced adenocarcinoma of stomach and gastroesophageal junction.

The TACiE protocol includes four cycles. Transcatheter oxaliplatin and concurrent embolism on day 1 and oral S-1 on day 1-14 will be administrated in the first and third cycles. Intra-venous oxaliplatin on day 1 and oral S-1 on day 1-14 (SOX) will be administrated in the second and fourth cycles.

Inclusion Criteria:

• Male or female, aged 18 to 75 years old;
• The Karnofsky Performance Scale (KPS) score >=80;
• Adenocarcinoma of stomach and gastroesophageal junction (Siewert II/III) diagnosed pathologically;
• clinical T3-4a/N+/M0 (The 8th edition of the American Joint Committee on Cancer (AJCC) staging system);
• According to the Response Evaluation Criteria In Solid Tumours (RECIST) 1.1 standard, there is at least one evaluable lesion in the abdominal CT/MRI;
• The surgeons participating in this study judged the lesion to be resectable;
• Physical condition allows the surgery;

Exclusion Criteria:

• Distant metastasis or local unresectable factors;
• Cytotoxic chemotherapy, radiotherapy, immunotherapy or radical surgery for the treatment of this gastric cancer, except for corticosteroids;
• Active autoimmune diseases or a history of autoimmune diseases;
• History of malignant tumors within 2 years;
• Gastrointestinal bleeding within two weeks prior to enrollment, or those with high bleeding risk;
• Gastrointestinal perforation and/or fistula occurred within 6 months before enrollment;
• Upper gastrointestinal obstruction or abnormal physiological function or suffering from malabsorption syndrome, which may affect the absorption of drugs;
• Weight loss >=20% within 2 months before enrollment;
• A history of the following lung diseases: interstitial lung disease, non-infectious pneumonia, pulmonary fibrosis, acute lung disease, etc.;
• Uncontrollable systemic diseases including diabetes, hypertension, etc.; Severe chronic or active infections requiring systemic antibacterial, antifungal or antiviral therapy, including tuberculosis, HIV infection, etc.;
• Untreated patients with chronic hepatitis B or chronic HBV carriers with hepatitis B virus (HBV) DNA exceeding 500 IU/mL, or hepatitis C virus (HCV) RNA positive patients should be excluded;
• Any of the following cardiovascular risk factors (refer to Research Guide);
• Known peripheral nerve disease >=NCI CTCAE Grade 1. However, patients with only the disappearance of the deep tendon reflex (DTR) need not be excluded;
• Moderate or severe renal damage [creatinine clearance equal to or lower than 50 ml/min (calculated according to the Cockcroft and Gault equation)], or serum creatinine> upper limit of normal (ULN); People with known dihydropyrimidine dehydrogenase (DPD) deficiency;
• Those who are allergic to any research drug ingredients;
• Underwent major surgery within 28 days prior to enrollment;