Stomach cancer is a common tumor in China, especially in rural areas. In the past, the treatment method of gastric cancer was often to operate first and then chemotherapy after surgery, and most of the patients died within one to two years because of metastasis and recurrence. For patients who underwent “switch” surgery as mentioned above, there is no good treatment method, and 100% of such patients will die of gastric cancer within a short period of time. The latest clinical studies and NCCN cancer treatment guidelines have shown that the best treatment for gastric cancer is surgery first, followed by simultaneous radiotherapy and chemotherapy, which can increase the 3-year absolute disease-free survival rate of gastric cancer by 17% and the disease-free survival rate by 54%, thus greatly improving the tumor treatment effect.