Treatment of myelodysplastic syndromes with 5-azacytidine

Abstract 

Patients with myelodysplastic syndromes (MDS) who were anemic and/or thrombocytopenic were treated with 5-azacytidine (5-AZA) at a dose of 75mg/m² per day SQ×7 days. This cycle was repeated every 28 days. Forty-eight patients who received at least one cycle of 5-AZA were evaluable for response. Hematological toxicity was mild and consisted of thrombocytopenia and leukopenia. Extramedullary toxicity was uncommon and consisted of pneumonia, arthralgia, diarrhea, and injection site irritation. Eighteen of the 46 transfusion dependent patients became transfusion independent (39%). Median duration of response was 7 months with three patients continuing beyond 2 years. French Anglo British (FAB) classification and the International Scoring System (ISS) did not predict response to 5-AZA. However, a decrease in the white blood cells (WBC) during the initial cycle of 5-AZA correlated with a higher response rate.

Abbreviations:  MDS, myelodysplastic syndromes, FAB, French Anglo British, ISS, International Scoring System, 5-AZA, 5-azacytidine, Ara-C, cytosine arabinoside, WBC, white blood cells, RBC, red blood cells, PLT, platelets, NSS, not statistically significant, CALGB, Cancer and Leukemia Group B, ECOG, Eastern Cooperative Oncology Group, IWG, International Working Group, RA, refractory anemia, RARS, refractory anemia with ringed sideroblasts, CMML, chronic myelomonocytic leukemia, RAEB, refractory anemia with excess blasts, RAEB-T, refractory anemia with excess blasts in transformation, G-CSF, granulocyte colony stimulating factor

Keywords:  Azacytidine, Myelodysplastic syndromes, Chemotherapy, Leukemia, Refractory anemia