Assessing Measurable Residual Disease in Chronic Myeloid Leukemia. BCR-ABL1 IS in the Avant-Garde of Molecular Hematology

Chronic myelogenous leukemia (CML) is a malignancy of the myeloid cell lineage characterized by a recurrent chromosomal abnormality: the Philadelphia chromosome, which results from the reciprocal translocation of the chromosomes 9 and 22. The Philadelphia chromosome contains a fusion gene called BCR-ABL1. The BCR-ABL1 codes for an aberrantly functioning tyrosine kinase that drives the malignant proliferation of the founding clone. The advent of tyrosine kinase inhibitors (TKI) represents a landmark in the treatment of CML, that has led to tremendous improvement in the remission and survival rates. Since the introduction of imatinib, the first TKI, several other TKI have been approved that further broadened the arsenal against CML. Patients treated with TKIs require sensitive monitoring of BCR-ABL1 transcripts with quantitative real-time polymerase chain reaction (qRT-PCT), which has become an essential part of managing patients with CML. In this review, we discuss the importance of the BCR-ABL1 assay, and we highlight the growing importance of BCR-ABL1 dynamics. We also introduce a mathematical correction for the BCR-ABL1 assay that could help homogenizing the use of the ABL1 as a control gene. Finally, we discuss the growing body of evidence concerning treatment-free remission. Along with the continuous improvement in the therapeutic arsenal against CML, the molecular monitoring of CML represents the avant-garde in the struggle to make CML a curable disease

Adult acute megakaryoblastic leukemia: rare association with cytopenias of undetermined significance and p210 and p190 BCR–ABL transcripts

Delia Dima,1,* Liana Oprita,2,* Ana-Maria Rosu,3,* Adrian Trifa,4 Cristina Selicean,1 Vlad Moisoiu,3 Ioana Frinc,1 Mihnea Zdrenghea,1,5 Ciprian Tomuleasa1,3,5 1Department of Hematology, Ion Chiricuta Oncology Institute, 2Department of Dentistry, 3Research Center for Functional Genomics and Translational Medicine, 4Department of Genetics, 5Department of Hematology, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania *These authors contributed equally to this work Abstract: Acute megakaryocytic leukemia (M7-AML) is a rare form of acute myeloid leukemia (AML), which is associated with poor prognosis. The case presented in the current report is a statement for the difficult diagnosis and clinical management of M7-AML in the context of a previous hematologic disorder of undetermined significance and associated genetic abnormalities. Probably, following the complete hematologic remission and further with induction chemotherapy plus tyrosine kinase inhibitor therapy, the clinical management of this case will be followed by a allogeneic bone marrow transplantation, the only proven therapy to improve overall survival. Keywords: acute megakaryocytic leukemia, BCR–ABL transcript&nbsp