Recombinant human erythropoietin (rHuEPO) is an effective treatment for the anaemia that occurs secondary to various conditions, but its role in myelofibrosis with myeloid metaplasia (MMM) is not well established. rHuEPO, at an initial dose of 10 000 U thrice a week, was given to 20 patients with MMM and anaemia. Complete response (CR) was defined as transfusion cessation with normal haemoglobin (Hb) levels and partial response (PR) as a transfusion decrease > or =50% and Hb > 10 g/dl maintained for at least 8 weeks. Nine patients (45%) showed a favourable response to treatment, including four CR and five PR, four of whom have maintained their response at a median follow-up of 12.5 months (range: 4-21 months) from the start of treatment. The pretreatment factors associated with a favourable response were lack of transfusion requirement (P = 0.002) and higher Hb at start treatment of (P = 0.01). An analysis of the present series (n = 20) and 31 patients from the literature identified 28 (55%) favourable responses to rHuEPO, including 16 CR and 12 PR. In the multivariate analysis, serum erythropoietin level <125 U/l was found to be associated with a favourable response to rHuEPO, whereas lack of transfusional support had borderline significance.