promyelocytic leukaemia (acute)
Acute promyelocytic leukaemia (APL) is a distinct subtype of AML which is characterised by the presence of many promyelocytes in peripheral blood and marrow aspirate.
- cells with a granular cytoplasm which stains brown with myeloperoxidase
- normally precursors of neutrophils, basophils, eosinophils and monocytes
APL accounts for approximately 5-15% of acute myeloid leukaemia (1).
The following are considered independent risk factors for the development of APL in a patient with AML:
- younger age
- Hispanic background
- obesity (1)
The major cause of mortality is bleeding, particularly intracranial, which may be exacerbated by chemotherapy.Although relatively rare, APL is important since it is the first cancer in which a specific treatment has been developed which targets the genetic defect responsible for tumorigenesis.
- (1) Jabbour EJ, Estey E, Kantarjian HM. Adult acute myeloid leukemia. Mayo Clin Proc. 2006 Feb;81(2):247-60.
- (2) NEJM 329(3):177 (1993)
- (3) Leukemia 8 Supp.2 (1994)
- (4) Lancet 344:1615 (1994)
Last reviewed 01/2018