Clinically, the early symptoms of gastric cancer do not include stomach pain, and usually patients do not have any obvious clinical symptoms in the early stage, only a very small number of patients may experience nausea and vomiting. Moreover, if the patient is in the progressive stage of gastric cancer, which is clinically not considered as early gastric cancer, he/she will experience pain and weight loss, and he/she will experience pain in the upper abdomen. Patients may also experience other symptoms, such as loss of appetite, weight loss, weakness, nausea, vomiting, feeling of fullness after eating, and some patients may also experience gastrointestinal bleeding such as vomiting blood and black stool. If the patient has swollen supraclavicular lymph nodes, ascites, jaundice, anemia, emaciation, or even cachexia, it is usually the case that gastric cancer has spread or metastasized, and the disease is more advanced at that time.