Abstract:
Background. Atypical chronic myeloid leukemia (aCML), BCR-ABL1 negative is a rare
myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) for which no current
standard of care exists. ACML is characterized by many clinical features (splenomegaly, myeloid
predominance in the bone marrow with some dysplastic features but without a differentiation
block) and laboratory abnormalities (myeloid proliferation, low leukocyte alkaline phosphate
values). A review of the literature suggests that the presence of an abnormal chromosome 21 may
predispose to the development of leukemia.