Current Management of Chronic Myeloid Leukemia Myeloid Blast Phase

Abstract

Despite the major advancements in the management of chronic phase (CP) chronic myeloid leukemia (CML), blast crisis (BC) remains a major therapeutic challenge. BC can be myeloid, lymphoid, or mixed lineage with myeloid BC being the most common type. BC in CML is mediated by aberrant tyrosine kinase activity of the BCR::ABL fusion protein. The introduction of BCR::ABL tyrosine kinase inhibitor (TKI) has been a gamechanger in the treatment of CML and there has been a significant reduction in the incidence of BC. The main treatment goal in BC is to achieve a second CP and consolidate that with an allogeneic stem cell transplantation (SCT) in eligible patients. The outcomes in BC remain dismal even in the current era. In this review, we provide an overview of the biology and current therapeutic approach in myeloid BC.

Keywords: Chronic myeloid leukemia; additional chromosomal abnormality; blast crisis; stem cell transplant; tyrosine kinase inhibitor.

Figure 1.

Algorithm for TKI selection in CP-CML. CML indicates chronic myeloid leukemia; CP, chronic phase; TKI, tyrosine kinase inhibitor.

Figure 2.

Optimal milestones in CML-CP therapy. CML indicates chronic myeloid leukemia; CP, chronic phase.

Figure 3.

Current management in CML myeloid BC. BC indicates blast crisis; CML, chronic myeloid leukemia; CP, chronic phase; HMA, hypomethylating agent; SCT, stem cell transplantation; TKI, tyrosine kinase inhibitor; FLAG-IDA, fludarabine,cytarabine,granulocyte colony stimulating factor (G-CSF), idarubicin.