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%).