Management of patients with myelodysplastic syndromes.

The myelodysplastic syndromes are composed of a group of clonal hematologic neoplasms, the course of which is complicated by ineffective hematopoiesis or leukemic transformation (or both). Therapeutic results may have been misleading in the past. Most patients have been managed with supportive measures, such as transfusions of erythrocytes, administration of antibiotics, and transfusions of platelets during active bleeding episodes. These supportive measures have prolonged and improved the quality of life of patients with myelodysplastic syndromes. Vitamin supplementation (folate, vitamin B12, and pyridoxine) has seldom been rewarding. Differentiation agents such as cis-retinoic acid and 1,25-dihydroxyvitamin D3 have been of benefit in only a limited number of patients. Androgens have not been useful, although danazol, which is an attenuated androgen, has been effective in a subset of patients with the presence of cell-bound platelet antibodies. Low-dose cytarabine, which has been studied extensively because of its differentiating activity in vitro, is associated with a generally low rate of complete remission and substantial toxicity. Antileukemic therapy is generally useful in young patients with rapidly progressive disease. Several hematopoietic growth factors are currently being evaluated in clinical trials; their use in combination or in conjunction with chemotherapy may be opening new horizons for these patients. With improvements in the prevention and treatment of graft-versus-host disease, allogeneic transplantation is a viable option for patients younger than 55 years of age who have severe cytopenias.