• Histologically proven adenocarcinoma of the stomach, PD-L1+(CPS≥1).

• Clinical cT3-4a/N+M0 disease, confirmed by upper gastrointestinal endoscopy and abdominal computed tomography (CT) and laparoscopy.

• The gastric tumors are macroscopically resectable by distal gastrectomy with D2 lymph node dissection, and R0 or R1 resection can be achieved.

• No bulky lymph node metastasis is detected by abdominal CT.

• No pleural effusion, no ascites exceeding the pelvis and no metastasis to the peritoneum, liver or other distant organs are confirmed by abdominal pelvic CT.

• No clinically apparent distant metastasis.

• Karnofsky performance status ≥70%.

• Sufficient oral intake.

• No previous treatment with chemotherapy or radiation therapy for any tumors.

⁃ No previous surgery for the present disease.

⁃ Sufficient organ function, as evaluated by laboratory tests 7 days or more after the date when the anticancer drugs were given. When patients are recovering from myelosuppression,the revised criteria are shown in parentheses. White blood cell count≥3000/mm3 (2000/mm3) Platelet count≥10.0\*104/mm3 (5.0\*104/mm3) Aspartate aminotransferase≤100 IU/l Alanine aminotransferase≤100 IU/l Total bilirubin≤2.0 mg/dl Serum creatinine≤1.5 mg/dl

⁃ No need for emergency surgery due to bleeding or perforation of the primary tumor.

⁃ No mechanical obstruction.

⁃ Written informed consent.