Case History

The patient is a 35-year-old-female with leukocytosis. Peripheral blood findings showed increased blasts consistent with acute leukemia. The morphology is suggestive of which genetic abnormality?


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The correct answer is D. CBFB-MYH11

The images show acute myeloid leukemia, as demonstrated by the increase in blasts. Also present, are scattered eosinophils with abnormal granulation, consisting of large eosinophilic and basophilic granules. This morphology is suggestive of AML with inv(16), which results in the fusion of CBFB at 16q22 to MYH11 at 16p13.1.  Morphologically, the abnormal granules occur at the late promyelocyte and myelocyte stages, rather than in the later stages of eosinophilic maturation. AML with inv(16), as well as AML with t(8;21), are both associated with a high rate of complete remission and favorable overall survival after treatment with high dose cytarabine.

Case contributed by: Danielle N. Fasciano, D.O., UAB Hematopathology Fellow