INV(16)(p13q22) - CBFB-MYH11
Abnormalities of chromosome 16 are found in about 5–8% of acute myeloid leukemia (AML). The AML with inv(16)(p13.1q22) or t (16;16)(p13.1;q22) is associated with a high rate of complete remission and favorable overall survival when treated with high-dose Cytarabine. This subtype of AML is typically associated with distinctive morphologic findings, including a prominent monocytic component, eosinophilia, and abnormalities involving immature eosinophilic granules in late promyelocyte and myelocyte stages of eosinophil maturation.
The inv(16) results in a leukemogenic CBFB/MYH11 gene fusion. In these rearrangements the core binding factor β (CBFB) gene on 16q22 is fused to the smooth muscle myosin heavy chain gene (MYH11) on 16p13.
The detection of the CBFB/MYH11 fusion gene by reverse transcriptase–polymerase chain reaction (RT-PCR) allows patients to be assigned to the appropriate risk group for management.