Whether or not p210 positive in chronic leukemia is serious needs to be decided according to the changes in the condition. A positive p210 for chronic leukemia indicates that the patient’s BCR-ABL fusion gene type is P210, and the test result is positive for the presence of the P210 fusion gene. The vast majority of patients with lentigo are of the P210 type, and very few are of the P190 type or other rare types. The following symptoms in patients with chronic leukemia indicate that the disease is serious and progressing: 1. unexplained fever, anemia and worsening bleeding, which may be accompanied by bone pain. 2. progressive enlargement of the spleen. 3. non-drug-induced thrombocytopenia or increase in platelets. 4. 10% to 20% of primitive cells in the blood or bone marrow. 5. presence of chromosomal aberrations other than Ph. 6. Ineffective treatment with anti-slow-growth leukemia chemotherapeutic agents (imatinib, dasatinib). 7. increase in CFU-GM culture clusters and increase in the ratio of clusters to colonies. If the condition of patients with P210-positive chronic leukemia begins to progress, it is recommended to go to the hospital in time and give targeted treatment or therapy under the guidance of physicians.