[Treatment for low-risk myelodysplastic syndromes]

Myelodysplastic syndromes (MDS) are clonal hematopoietic stem cell disorders characterized by cytopenia and leukemic transformation. Allogeneic hematopoietic stem cell transplantation is the only potential curative therapy for MDS; however, the first treatment option for transfusion-independent patients with low-risk MDS remains limited. Recently, lenalidomide has become available for patients with low-risk MDS and symptomatic anemia with del (5q) (5q-syndrome), darbepoetin (DA) for those with anemia without del (5q), and azacitidine for those with DA-resistant anemia or anemia with thrombocytopenia. DA may be the first treatment option for anemic patients with low-risk MDS because the incidence of 5q-syndrome is rare in Japan in contrast to western countries. It has been reported that primary or secondary failure of Erythropoiesis-stimulating agents (ESA) correlated with a higher risk of acute myeloid leukemia, and none of the leading second-line treatments significantly improved survival. In this review, I have described the treatment strategies in using such drugs and future perspectives for low-risk MDS.