Bone marrow transplant in myelodysplastic syndromes: new technologies, same questions.

Myelodysplastic syndrome (MDS) comprises a heterogeneous group of hematologic disorders characterized by a clonal abnormality of hematopoietic stem cells that results in a varying degree of cytopenias and risk of transformation into acute leukemia. Only allogeneic transplant has been shown to cure this disease. However, high nonrelapse mortality rates limit the applicability of conventional allografts and, even in young patients, long-term disease control ranging from only 30% to 50% has been reported. Novel transplant regimens, availability of alternative donors, and busulfan targeting promise to increase transplant applicability and reduce nonrelapse mortality rates. However, high relapse rates in patients with high-risk disease limit the success of this procedure to the point that a definite advantage of allografting over standard therapy remains controversial. New agents being developed for MDS may have a potential impact on transplant outcomes. Therefore, design and implementation of clinical trials of transplant for MDS should be encouraged to improve the natural history of this disease.