Chronic myeloid leukemia

Chronic myeloid leukemia is a malignant clonal disorder of hematopoietic stem cells.

At presentation, one-third of patients may be asymptomatic; if present, symptoms typically include malaise, fever, weight loss, abdominal discomfort, and night sweats.

Splenomegaly is the most common physical finding; nearly all patients will have elevated WBC count.

Presence of Philadelphia chromosome and /or molecular demonstration of the BCR-ABL transcript confirms diagnosis.

Treatment with a BCR-ABL tyrosine kinase inhibitor (TKI) gives long-term remission without significant adverse events in most patients.

Treatment-free remission may be attempted for select patients, and thus functional cure after TKI therapy is feasible.

Chronic myeloid leukemia (CML) is a malignant clonal disorder of the hematopoietic stem cell that results in marked myeloid hyperplasia of the bone marrow.[1]Sawyers C. Chronic myeloid leukemia. N Engl J Med. 1999 Apr 29;340(17):1330-40. http://www.ncbi.nlm.nih.gov/pubmed/10219069?tool=bestpractice.com Dysregulation of hematopoiesis arises due to a BCR-ABL fusion gene that causes an abnormal expansion of myeloid cells in the bone marrow and peripheral blood. The “chronic phase” of the disease may transform to an “accelerated” or “blast” phase in 5% to 10% of patients despite treatment with a tyrosine kinase inhibitor, the latter resulting in acute myeloid or acute lymphoblastic leukemia (ALL).[2]Hochhaus A, O'Brien SG, Guilhot F, et al. Six-year follow-up of patients receiving imatinib for the first-line treatment of chronic myeloid leukemia. Leukemia. 2009 Jun;23(6):1054-61. http://www.ncbi.nlm.nih.gov/pubmed/19282833?tool=bestpractice.com [3]Druker BJ, Guilhot F, O'Brien SG, et al. Five-year follow-up of patients receiving imatinib for chronic myeloid leukemia. N Engl J Med. 2006 Dec 7;355(23):2408-17. http://www.nejm.org/doi/full/10.1056/NEJMoa062867#t=article http://www.ncbi.nlm.nih.gov/pubmed/17151364?tool=bestpractice.com