Acute myeloid leukemia with myelodysplasia-related changes mimicking acute promyelocytic leukemia

We describe a patient with acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) that clinically resembled acute promyelocytic leukemia (APL). The karyotype of his leukemic cells was 46, XY, del (3) (q?) and did not include a chromosomal translocation involving the retinoic acid receptor-α gene. However, retinoic acid syndrome developed, and partial remission was achieved after treatment with all-trans retinoic acid (ATRA) followed by chemotherapy. Our case might provide new insights into the mechanism of the growth inhibitory effect of ATRA on APL-like cells.