The chronic myeloid leukemia (CML) is classically staged into chronic phase (CP, most patients at presentation), accelerated phase (AP) and blast phase (BP). Many definitions have been used for these stages, but all the data generated from the tyrosine kinase inhibitor (TKI) studies has used the historically standard definition where AP is defined by the presence of one or more of the following: ≥15% blasts in PB/BM, ≥20% basophils in PB, platelets <100,000/µL unrelated to treatment or the development of cytogenetic evolution. Blast phase is defined by the presence of ≥30% blasts in the peripheral blood or bone marrow, the presence of clusters of blasts in marrow or the presence of extramedullary disease with immature cells (i.e., a myeloid sarcoma). Continue reading “Accelerated Phase Criteria for Chronic Myeloid Leukemia (CML)”