S-HAM induction chemotherapy with or without GM-CSF in patients with high-risk myelodysplastic syndromes

Thirty-one adult patients with high-risk myelodysplastic syndromes (MDS) were enrolled in a prospective randomized double-blind placebo-controlled trial evaluating the efficacy of sequential high-dose Ara C/mitoxantrone chemotherapy with or without GM-CSF. GM-CSF or placebo was given subcutaneously once daily at a dose of 250 micrograms/m2 starting 48 h prior to chemotherapy and continued until neutrophil recovery. This design allowed us to investigate the role of GM-CSF as a priming factor for the leukemic clone, as well as its effect on the recovery of normal hematopoiesis. Twenty-eight patients are currently evaluable for response. The patients reached a complete remission (36%), eight patients had persistent MDS (29%), and ten patients died within 6 weeks after the onset of treatment (early death). Infectious complications during cytopenia were the major cause of death (8/10). Median time to complete hematologic recovery (neutrophils > 500/microliter and platelets 20,000/microliter) and time to neutrophil recovery above 1500/microliter was 29 and 35 days, respectively. Median remission duration was 190 days (6.4 months). Analysis of prognostic subgroups showed a low CR rate (25%) and a high early-death rate (44%) in patients > 55 years of age, suggesting that the intensified treatment approach should be limited to younger patients. No data concerning the influence of GM-CSF on response to chemotherapy or duration of neutropenia are presently available.