Granulocyte–Macrophage Colony-Stimulating Factor and Myelodysplastic Syndromes

To the Editor: Vadhan-Raj and coworkers (Dec. 17 issue) ¹ have demonstrated a stimulatory effect of granulocyte–macrophage colony-stimulating factor (GM-CSF) in several patients with myelodysplastic syndromes, both primary and therapy-related. It is encouraging to note the increase in both erythropoiesis and thrombopoiesis. Infections account for at least 50 percent of all deaths among patients with myelodysplastic syndromes. This is a result of both qualitative abnormalities of granulocytes and low production of normal neutrophils.² However, there is no mention of the qualitative changes in granulocytes (e.g., pseudo-Pelger cells or hypogranular neutrophils), or whether there was a change toward normal maturation or merely.