Atypical chronic myeloid leukaemia (aCML) is a rare myelodysplastic/myeloproliferative (MDS/MPN) neoplasm morphologically characterised by leukocytosis, immature granulocytes in the peripheral blood (PB) and granulocytic and megakaryocytic dysplasia in the bone marrow (BM).1 Blast crisis is frequent and associated with an exceedingly poor prognosis.2 Allogeneic stem cell transplantation is the only potentially curative option but in those patients ineligible, treatment has largely relied on...