Early stage stomach cancer may not have any symptoms, while advanced stomach cancer or may present with abdominal or mid-abdominal discomfort or pain, or even symptoms such as black stools, vomiting or vomiting blood, and difficulty in swallowing. Early stage stomach cancer can usually have no symptoms, and even if it does, the symptoms may be due to the combination of atrophic gastritis, functional dyspepsia, or H. pylori infection, rather than being caused by the stomach cancer lesion itself. As the disease progresses, patients may have symptoms such as persistent pain, nausea and vomiting, black stools, vomiting blood, abdominal mass, etc. Patients with advanced gastric cancer usually suffer from progressive malnutrition, significant weight loss in a short period of time, and symptoms such as anemia and edema. In addition, unexplained loss of appetite and fatigue occur. Abdominal discomfort, dyspepsia, irregular or unshaped bowel movement after more than 5 years of previous gastric surgery should be considered as gastric cancer.