First-Line and Neoadjuvant Immunotherapy for Gastric Cancer

Inclusion Criteria: 1. Age 18 years old or above 2. Patients with advanced gastric cancer or locally advanced gastric cancer 3. Have not received any previous anti-tumor therapy 4. Patients expected to receive immunotherapy for first-line or neoadjuvant therapy 5. Eastern Cooperative Oncology Group (ECOG) performance status of 0-1 6. Adequate organ function Exclusion Criteria: 1. Patients with contraindications to immunotherapy 2. Have received anti-tumor treatments such as immunotherapy and chemotherapy 3. Have a history of active immune deficiency or autoimmune diseases, including HIV positive test, or have other acquired or congenital immune deficiency diseases, or have a history of organ transplantation or autoimmune diseases 4. Severe chronic or active infection requires systemic antibacterial, antifungal, or antiviral treatment, including tuberculosis infection. Have a history of active tuberculosis infection ≥ 1 year before recruitment should also be excluded, unless proved has been completed appropriate treatment 5. History of allogeneic stem cell transplantation or organ transplantation