A Case of Atypical Chronic Myeloid Leukemia with the JAK2V617F Mutation

ABSTRACT

Atypical chronic myeloid leukemia (aCML) is a rare leukemic disorder that shows myelodysplastic and myeloproliferative features simultaneously. The Janus kinase 2 gene V617F mutation (JAK2V617F) in aCML has been the source of much controversy. Some JAK2V617F positive cases have been reported but others observed no JAK2V617F mutation in aCML as defined by WHO classification. Recently, we experienced a case of aCML with JAK2V617F mutation with typical myelodysplastic/myeloproliferative features in peripheral blood and bone marrow aspirates. The karyotype was normal and no BCR/ABL1, PDGFRA or PDGFRB gene rearrangement was noted with FISH analysis. JAK2V617F mutation of the case was identified with amplification refractory mutation system PCR and direct sequencing. We also studied JAK2V617F mutation status in 3 additional cases of previously diagnosed aCML in our institution, but no mutation was identified.