BCR-ABL Testing by Polymerase Chain Reaction in Patients With Neutrophilia: The William Beaumont Hospital Experience and the Case for Rational Laboratory Test Requests.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm resulting from the fusion of the BCR-ABL genes, forming the Philadelphia chromosome. The diagnosis is often suspected when there is leukocytosis with left shift and basophilia. Confirmation of the diagnosis requires a demonstration of BCR-ABL by polymerase chain reaction.