Background: We report three cases of juvenile myelomonocytic leukemia in children. Juvenile myelomonocytic leukemia (JMML) is a rare myeloproliferative disorder of childhood, representing 1-2%
of all leukaemias, with characteristic clinical and laboratory findings.Case Report: Clinical symptoms at a time of diagnosis included fever, frequent viral infections, hepatosplenomegaly, lymph node enlargement and cutaneous xanthogranuloma. Hematological findings were characterized by thrombocytopenia, leukocytosis with an increase of mature and immature myeloid cells and monocytes in the absence of the Philadelphia chromosome. One patient had deletion in chromosome 7 and another increased HbF concentration. Different treatment strategies including low dose chemotherapy, intensive AML therapy and /orretinoids were employed to treat our patients with only transient regression of the disease. One patient underwent the allo-BMT procedure which was complicated with early relapse. Intensive chemotherapy was complicated with severe toxicities. Among our patients the younger 3- month- old, had the longer survival of 2 years. Two other patients died 7,5 and 12 months from diagnosis.Conclusions: The treatment of JMML continues to generate controversy. Regardless of the type of treatment regimen, chemotherapy never results in complete remission. Also, neither splenectomy nor radiotherapy is of value in the treatment of JMML. Currently, bone marrow transplantation (BMT) is the therapy of choice that clearly improves outcome in the clinical management of JMML, but is associated with high transplant related mortality (TRM) and a high relapse rate.

Keywords: JMML, BMT, myeloproliferative disorders