Successful re-treatment with azacitidine in a patient with low blast count AML transformed from MDS after suspension of this agent

TO THE EDITOR: The treatment approach to acute myeloid leukemia (AML) transformed from high-risk myelodysplastic syndrome (MDS) after azacitidine failure is not standardized and the clinical results achievable in this setting are generally disappointing [1,2,3]. Similarly, poor outcomes have also been reported in the setting of AML transformation following azacitidine discontinuation due to reasons other than hematologic progression in MDS patients initially responding to hypomethylating therapy [4]. Little is known of azacitidine-responsive MDS patients who progressed to AML with 20-30% bone marrow (BM) blasts after suspension of this agent, nor of the possibility to re-induce hematological control after the resumption of hypomethylating therapy.