Standards for the diagnosis and treatment of chronic myeloid leukemia

Paulo Campregher
J. Bras. Patol. Med. Lab. 2018;54(2):68
DOI:10.5935/1676-2444.20180023

ABSTRACT

Myeloproliferative disorders are a group of clonal myeloid neoplasms characterized by increased proliferation of myeloid cells with preserved cell differentiation. The molecular features of myeloproliferative neoplasms have been efficiently mapped in the last decades(1). Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm defined by the presence of t(9;22)(q34;q11), a BCR-ABL1 gene fusion, and characterized by three distinct clinical-laboratorial phases: a chronic phase (CP) with leukocytosis, left shift, basophilia, eosinophilia, thrombocytosis, and no increase in blast counts; an accelerated phase (AP) characterized by increasing in blast count and additional cytogenetic changes; and a blastic phase (BP) characterized by more than 20% blasts in the bone marrow. The management of CML represents one of the major advances in the history of medicine with the transformation of a highly lethal condition into a chronic disease managed, most of the times, with one pill a day. Although rare, with an incidence of 1.6 per 100,000(2), the estimated 8-year survival of CML in CP used to be 6% before 1975. After the discovery of tyrosine kinase inhibitors for CML treatment the 8-year survival became 87% since 2001(3). The correct diagnosis and monitoring of CML involve distinct laboratorial techniques such as complete blood counts, bone marrow morphological analysis, conventional cytogenetics, fluorescence in situ hybridization and real time polymerase chain reaction (PCR). In order to achieve this highly successful treatment strategy, the correct diagnosis and laboratorial monitoring are crucial. Read more…