[Juvenile myelomonocytic leukemia: A three-case series].

Juvenile myelomonocytic leukemia (JMML), previously known as juvenile chronic myeloid leukemia (JCML), is a rare, myelodysplastic-myeloproliferative disease typically presenting in early childhood. This disorder is difficult to distinguish from other myeloproliferative syndromes such as chronic myeloid leukemia (CML) because of the similarities in their clinical and bone marrow findings. However, because of its unique biological characteristics such as absolute monocytosis with dysplasia, absence of Philadelphia chromosome or BCR-ABL fusion protein, hypergammaglobulinemia, and raised fetal hemoglobin level, this disorder does not satisfy the criteria for inclusion in the CML or chronic myelomonocytic leukemia (CMML) group, as seen in adult patients. We describe three cases of JMML, who had very similar clinical and laboratory findings.