Treatment with cytosine arabinoside and granulocyte colony-stimulating factor in patients with myelodysplastic syndrome and its leukemic phase.

Twenty-one patients with myelodysplastic syndrome (MDS) or overt leukemia resulting from MDS were treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cytosine arabinoside (Ara-C). Ara-C was administered in a dose of 20 mg/m2 every 12 h for 5 days and after 2 days 125 micrograms of rhG-CSF was administered for 10 days. After recovery of the leukocyte count the therapy was repeated, doubling the dose of Ara-C serially when possible. Of 13 patients with MDS, four achieved complete remission (CR), two good response (GR), two minor response (MR), and five no response (NR). Of eight patients with overt leukemia from MDS, only one with hyperplastic bone marrow achieved a partial response (PR) and the remaining seven achieved NR. The efficacy of the combination of rhG-CSF and Ara-C in the treatment of MDS and its leukemic phase is discussed, including at which time rhG-CSF should be administered: before, after or concomitantly with Ara-C. Multicenter randomized studies are needed in the evaluation of this combination therapy.