Gastrointestinal Stromal Tumor (GIST) is uncommon disease with only about 3,000 to 6,000 cases diagnosed annually. Tumors can occur in any sites in gastrointestinal tract, especially in stomach (60-70%) and small intestine (20-30%) and in large intestine and oesophagus, sometime in omentum, mesenterium, behind peritonaeum, etc. The disease is common in male from 40 to 80 years old. GIST is detected randomly during examinations such as endoscopy, X-ray or CT scan of stomach, large intestine. Tumors have two kinds of cell: lozenge cell (70%) and epithelial cell (30%). GIST is divided into 4 stages. Each stage has suitable treatments as chemical therapy, radio therapy, and targeted therapy. For metastatic GIST, tumors can be removed by surgery. The 5 years survival rate is 34% in removal tumors and is 10% in remained tumors