It has been recently demonstrated that erythropoietin increases the haemoglobin levels in anemia secondary to chronic renal failure. Moreover some recent experiences also suggested a possible role in the treatment of MDS. From April 1990 to April 1992, 23 patients (16 males and 7 females, median age 63.5 years) affected with low risk myelodysplastic syndrome (MDS) were treated with recombinant human erythropoietin (rHuEPO) to ameliorate Hb levels and transfusional requirement. All patients received high doses of rHuEPO (800 U/Kg weekly s.c. in 2-3 divided doses, for 3 months). A complete remission, defined as stable normalization of Hb level, was achieved in 1/23 patients. This patient had refractory anemia, by FAB criteria. A partial response, defined as stable increase of Hb levels > or = 1 g/dl and/or reduction of transfusional requirement > or = 50% lasting at least 3 months, was achieved in 7/23 patients. Patients with a partial response received rHuEPO at increased dosages (1200 U/Kg weekly s.c. 2-3 times): 1/7 achieved a complete response, 4/7 remained stable and 2/7 decreased to pre-therapy Hb value. These results suggest that rHuEPO may be a promising therapeutic tool for some MDS patients.