Erythroleukemia showing early erythroid and cytogenetic responses to azacitidine therapy

Abstract

Dear Editor, Hypomethylating agents exert cytotoxic effects and induce differentiation of hematopoietic cells. Azacitidine therapy for myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) with multi-lineage dysplasia resulted in a significant survival advantage over conventional treatment [1–3]. Nevertheless, its efficacy against a specific subtype of MDS/AML has not been fully unveiled. Here, we characterize the response to azacitidine therapy in patients with erythroleukemia. The first case is a 79-year-old male presenting with progressive pancytopenia and red cell transfusion dependency. His hemoglobin level was 82 g/L, white blood cell (WBC) count 1.8×10/L with 1.5 % blasts, platelet count 5.5×10/L, and erythroblast count 27 per 100 WBCs. The bone marrow was hypercellular with multilineage dysplasia and erythroid dominance (Fig. 1a). Myeloblasts accounted for 40 % of non-erythroid cells