Feasibility of hypomethylating agents followed by allogeneic hematopoietic cell transplantation in patients with myelodysplastic syndrome.

The role of hypomethylating agent therapy (HMT) as a bridge to allogeneic hematopoietic cell transplantation (alloHCT) in patients with myelodysplastic syndrome (MDS) remains undetermined. We investigated the feasibility of HMT followed by alloHCT in patients with MDS. In all, 19 patients who received HMT followed by alloHCT were analyzed. A total of 7 patients were classified as low-risk and 12 as high-risk, based on World Health Organization (WHO) classification at the time of HMT. HMT consisted of decitabine in 9 patients and azacitidine in 10. After HMT, two patients achieved CR, six mCR, three hematologic improvement alone, and six SD in terms of best response. HMT did not alter WHO classification in 15 patients (79%), whereas 1 patient (5%) improved and 3 (16%) progressed to AML. Most patients (95%) received a non-myeloablative conditioning regimen based on fludarabine/BU/anti-thymocyte globulin, and peripheral blood-mobilized stem cells. Neutrophil and platelet engraftments were achieved in 95 and 79% of patients, respectively. The incidences of acute and chronic GVHD were 42 and 26%, respectively. In all, 2-year OS rates were 68%, and the overall outcomes of those who achieved CR/mCR with HMT tended to be superior to those without CR/mCR. HMT followed by alloHCT was a feasible and effective treatment strategy for patients with MDS.