The symptoms of gastric cancer patients are generally common gastrointestinal symptoms such as nausea, vomiting, acid reflux, and discomfort and bloating in the upper abdomen, especially aggravated after eating. As the condition progresses, symptoms may include vomiting blood or black stools. When the cancer invades surrounding organs, clinical symptoms such as abdominal effusion, abdominal distension, and pain may occur. If the tumor is located near the pylorus and causes pyloric obstruction, symptoms of pyloric obstruction will appear, such as gastric retention, acid reflux, and vomiting of overnight food. Additionally, if the tumor bleeds, it may cause severe vomiting of blood. Therefore, different stages of the disease present different symptoms. If gastric cancer progresses to the late stage with metastasis to distant organs, clinical manifestations corresponding to the sites of metastasis will also appear.