#00060848

This is a fifty-four year old woman status post arsenic and ATRA therapy for newly diagnosed acute promyelocytic leukemia (APL).

Bone marrow smear shows megaloblastoid changes and abnormal nuclear segmentation in erythroid precursors. Myeloid maturation and megakaryocytes were morphologically unremarkable without evidence of any leukemic promyelocytes.

Dysplastic changes are known to occur with arsenic and the observed changes sometimes mimic myelodysplastic processes. Hence, careful attention to the clinical history is essential to avoid misdiagnosis as MDS.