Table 1 Patient eligibility — inclusion and exclusion criteria

 • Ambulatory male or female aged 70 and above

 • Karnofsky score ≥ 70%

 • Histologically proven gastric adenocarcinoma in biopsy (including Lauren classification) Proven clinical stage of cT2-4aNanyM0 by baseline ultrasound endoscope, enhanced CT/MRI examination, or diagnostic laparoscopy using Habermann Standards

 • No past chemotherapy or radiotherapy before diagnosis

 • Primary tumor located at stomach, achievable naked-eye complete resection (R0/1) via distal subtotal or total gastrectomy plus lymphadenectomy

 • Haematology and biochemistry index meet the following: hemoglobin≥80 g/L, absolute neutrophils count (ANC) ≥ 1.5 × 109/L, platelet≥100 × 109/L, ALT、AST ≤ 2.5 times the upper limit of normal value, ALP ≤ 2.5 times the upper limit of normal value, serum total bilirubin< 1.5 times the upper limit of normal value, serum creatinine< 1 times the upper limit of normal value, serum albumin≥30 g/L

 • Heart and lung function can withstand surgery

 • No severe concomitant disease that leads to survival< 3 years

 • Willing and able to comply with study protocol

 • Written agreement consent before enrolment and full aware of the right to quit the study at any time with no loss

• Uncontrolled seizure, central nervous system diseases, or mental disorders;

• Past history of upper abdominal surgery (except for laparoscopic cholecystectomy)

• Past history of gastric surgery (including diagnosis procedure such as ESD and EMR)

• Other malignant diseases in 5 years (except for cured skin carcinoma and cervical carcinoma in situ)

• Clinical severe or active heart diseases, such as symptomatic coronary heart disease, NYHA grade II or above congestive heart failure, severe arrhythmia, or myocardial infarction in 6 months

• Cerebral hemorrhage or infarction in 6 months

• Organ transplant recipients under immunosuppressive therapy

• Severe uncontrolled repeated infection or other severe uncontrolled concomitant diseases

• Medium or severe renal damage (creatinine clearance rate ≤ 50 ml/min or serum creatinine> upper limit of normal value)

• Other diseases requiring synchronous surgery

• Requiring emergent surgery due to oncologic emergent (e.g. bleeding, perforation, obstruction)

• FEV1 < 50% of expected value

• Participated in other studies 4 weeks before the randomization.