The treatment of myelodysplastic syndromes.

The available data fail to support a standard therapy for MDS. Any therapy should therefore, include participation in a well designed clinical trial. The MDS include patients with a variety of prognoses. Since most studies show that death from infection and bleeding are more likely than progression to frank leukaemia, attention to supportive care is crucial for all patients with MDS. Some patients with MDS may be successfully supported with transfusions and observation for prolonged periods. Patients with significant comorbid disease or patients without increased marrow myeloblasts are good candidates for this conservative approach. Conversely, young patients have a better likelihood of benefit from aggressive therapy, and intensive chemotherapy or allogenic bone marrow transplantation should be considered. Patients with preleukaemia related to prior cytotoxic therapy are another poor prognosis group for whom aggressive therapy may be the best alternative. Therapy with low-dose ara-C or other differentiating agents should be considered investigational and unproven until comparative trials can demonstrate a definitive survival advantage. In addition to comparative trials, innovative clinical studies are needed to address differentiation as an in vivo mechanism of action and its importance in MDS therapy.