Diagnosis
Acute promyelocytic leukemia can be distinguished from other types of AML based on morphologic examination of a bone marrow aspirate or biopsy as well as finding the characteristic rearrangement. Definitive diagnosis requires testing for the PML/RARα fusion gene. This may be done by polymerase chain reaction (PCR), fluorescent in situ hybridization (FISH), or conventional cytogenetics of peripheral blood or bone marrow. This mutation involves a translocation of the long arm chromosomes of 15 and 17.
RARα is a member of the nuclear family of receptors; its ligand, retinoic acid is a form of Vitamin A and acts as a regulator of DNA transcription at multiple sites.
Monitoring for relapse using PCR tests for PML/RARα transcript allows early re-treatment which is successful in many instances.
Read more about this topic: Acute Promyelocytic Leukemia