Gastric cancer is divided into four stages, early stage I, intermediate stage II and III, and advanced stage IV, in which patients develop distant metastasis, including peritoneal metastasis, and the prognosis is poor. According to clinical experience, the five-year survival rate of patients with mid-stage gastric cancer is about 40%-50%. For malignant tumors, even if radical surgery is performed, the survival period still varies from person to person, which is related to the degree of malignancy of the tumor, whether there is lymph node metastasis, the overall immune status of the patient and whether the patient is sensitive to postoperative chemotherapy.