Gastric cancer is a malignant tumor originated from gastric mucous membrane epithelium. For early stage gastric cancer, most of them have no obvious symptoms, and a few of them have nausea, vomiting, or gastric ulcer-like epigastric symptoms, which are usually hard to cause enough attention, thinking that it is chronic gastritis and other diseases. As the disease progresses and tumor grows, when it affects the gastrointestinal tract, more obvious symptoms appear, such as: 1. Pain and weight loss are the most common symptoms of progressive gastric cancer.2. Decrease in appetite and fatigue.3. Symptoms such as vomiting blood, blood in stool and black stool can be found.4. Cancer of cardia of stomach can be characterized by symptoms such as retrosternal pain and progressive dysphagia.5. Symptoms of pyloric obstruction can be found in cancers near pylorus. When there are metastases in lymph nodes, enlarged lymph nodes can be touched in the left clavicle.7. There are also some symptoms caused by spreading of tumor, such as ascites, jaundice and other symptoms caused by metastases to various organs.