The location in the middle of the chest includes the stomach, the lower esophagus, and the left outer lobe of the liver. Therefore, when pain occurs in the subxiphoid process and the upper abdomen, it is very likely to consider stomach diseases, which may be gastritis, gastric ulcer, or gastric cancer, and gastroscopy is needed for further clarification. If inflammation of the mucous membrane in the stomach cavity is detected by gastroscopy, it suggests gastritis; if ulcerative lesions can be detected, it suggests gastric ulcer; if a lump or a depressed lesion with a bulge around it is detected, it generally suggests gastric cancer, and a small amount of tissue needs to be taken out for pathological examination after gastric cancer is suspected. Gastritis and gastric ulcer can be treated conservatively by internal medicine.