Additional rearrangements affecting the derivative chromosome 9 involved in the standard Philadelphia translocation after imatinib therapy in a patient with chronic myeloid leukemia.

摘要

Imatinib is a selective BCR-ABL tyrosine kinase inhibitor that has shown significant activity against Philadelphia-positive chronic myeloid leukemia (CML). Although the majority of CML patients in chronic phase have durable hematologic and cytogenetic responses to imatinib, a subset of CML patients lose their best response despite continued treatment. Some of these patients progress to accelerated phase or blast crisis, but some relapse . Here, we describe the novel case of a patient with CML, in which a standard Ph translocation transformed into a second translocation between chromosomes der(9) and der(21) accompanied by relapse and resistance after a brief disappearance of Ph chromosome subsequent to imatinib therapy.