ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The development of tyrosine kinase inhibitors (TKIs) for the treatment of chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) has led to the introduction of a selective targeted therapy that inhibits the BCR::ABL1 tyrosine kinase and to an improvement in treatment outcomes by suppressing the growth of leukemia cells (1).