Leukemia is a malignant tumor of the blood system. 1. Leukemia originates from the abnormal clonal proliferation of hematopoietic stem cells and hematopoietic progenitor cells. It is a systemic disease that mainly involves the blood system, and with the progress of the disease, it also involves the lungs, bones or other organs. 2. The cause of this disease is not clear, after high-dose radiotherapy and chemotherapy, suffering from 21-trisomy syndrome, viral infections and other diseases, long-term exposure to benzene and organic solvents containing benzene, and patients with a family history of leukemia are the factors of high incidence of this disease. 3. Patients may have a sudden high fever similar to a cold, or they may show severe bleeding, and slow patients often show pale face, ecchymosis and petechiae on the skin, and it is difficult to stop bleeding after menstruation or tooth extraction. 4. The treatment principle of this disease is to reduce the symptoms and control the development of the disease, and to kill the leukemia cells by chemotherapy as early as possible. Specific drugs include cytarabine, cyclophosphamide, vinblastine, zorubicin and so on. When the body has abnormalities in time to the regular hospital consultation and examination, so as not to delay the condition to miss the best treatment period, the use of drugs under the guidance of a physician.