Immunonutritional Supplement After Total Gastrectomy in Patients With Stage III Gastric Cancer

Inclusion Criteria: 1. Informed consent of patients or their legal representatives to participate in this study 2. consecutive adult (≥18 years) patients underwent radical gastrectomy (total gastrectomy) with pathological TNM stage III 3. nutrition Risk Screening (NRS) 2002≥3 at discharge 4. eastern Cooperative Oncology Group (ECOG) score of 0-2 at discharge Exclusion Criteria: 1. unable to oral or consume ONS 2. has received neoadjuvant chemotherapy 3. pregnancy 4. palliative surgery or gastric stump cancer or Borrmann type IV 5. oral anticoagulants cannot be stopped; congenital acquired immune deficiency disease 6. serious cardiovascular disease including chronic heart failure, angina pectoris, myocardial infarction, arrhythmias (such as atrial fibrillation), or uncontrolled hypertension 7. severe liver and kidney diseases including active hepatitis, cirrhosis, and uremia 8. diabetes has developed complications or uncontrolled by medications 9. previous use of drugs affecting immune function 10. previous use of fish oil capsule \> 2 times / week or contraindications to fish oil capsule 11. motor system diseases cannot complete grip strength measurement and 5-time chair stand test