ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Chronic myeloid leukemia (CML) is a hematologic stem-derived malignancy characterized by the presence of a specific chromosomal translocation (chromosome 9, 22) known as the Philadelphia chromosome (Ph), leading to the constitutive activation of the breakpoint cluster region-abelson (BCR-ABL) tyrosine kinase, which plays a crucial part in the pathogenesis of CML (1, 2).