Thalidomide for the treatment of patients with myelodysplastic syndromes.

We examined the efficacy of thalidomide in 34 patients with myelodysplastic syndromes (MDS): five RAEB-T, four RAEB, three CMML, six RARS, and 16 RA. Patients belonged to the following cytogenetic groups: 15 complex abnormal karyotypes, 12 normal karyotypes, four cases with 5q- as sole anomaly and three single aberrations. The median thalidomide dose was 400 mg/day (25/34 patients). Four patients discontinued the study after less than 5 weeks, because of fatigue (three) or skin rash (one). One patient died of heart failure after 4 weeks. In the remaining 29 patients (median follow-up: 13 months), treatment responses were classified according to the IWG criteria. Six patients (four RA, two CMML) showed progressive disease (five with transformation into AML) and four patients showed stable disease. Hematological improvement (HI) was observed in 19 patients. Nine of the responders (three RA, one RARS, two RAEB, three RAEB-T) achieved partial remission with granulocytes > or = 1500/microl, Hb > 11 g/dl and platelets > or =100,000/microl. Four patients (one RARS, one CMML, one RAEB, one RAEB-T) had a major response, with platelet and RBC transfusion independence. Six patients (five RA, one RARS) showed minor responses (three HI-E, two HI-E+HI-P, one HI-E+HI-N). Hematological improvement occurred after a median of 2 months of thalidomide treatment. Two patients (RAEB-T) relapsed after a partial remission lasting 8 and 16 months, respectively. In summary, a therapeutic benefit was achieved in 19 of 34 study patients (56%).