Abstract
Chronic myeloid leukemia with a significant increase of monocytes is rare and difficult to identify from chronic myelo-monocytic leukemia in clinic. A 31-year-old male patient with systemic pain was initially diagnosed as chronic myelo-monocytic leukemia, who was finally diagnosed as chronic myeloid leukemia by fusion gene and chromosome examination. In addition to the typical Ph chromosome, a rare chromosome translocation t(2; 7)(p13; p22) was observed. The detection of monocyte subsets by multi-parameter flow cytometry is a diagnostic marker to distinguish the above 2 diseases. The relationship between fusion genes and mononucleosis is not clear. Tyrosine kinase inhibitors or allogeneic hematopoietic stem cell transplantation can be used in the treatment for this disease.