USE OF GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR IN PATIENTS WITH MALIGNANCY AND BONE-MARROW FAILURE

Recombinant human granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) was administered to 10 patients with refractory malignancies, 2 patients who had myelodysplastic syndromes with severe neutropenia and to a patient who had delayed marrow recovery after 3 cycles of therapy for acute leukemia. A marked neutropenia and monocytopenia was observed within 5 min after an i.v. injection of GM‐CSF. This persisted for 1–2 h and seemed related to activation of an adhesive glycoprotein (MO1) on the surface of these cells. With continued daily i.v. administration of GM‐CSF, all patients with refractory malignancies developed a striking leukocytosis. Total leukocyte counts reached 75,000/m̈l within 2 weeks of treatment. This was due to an increase in band and segmented neutrophils, eosinophils and monocytes. Accelerated myelopoiesis required the continuous presence of GM‐CSF; with pump failure for 24 h or discontinuation after 14 days, leukocyte counts returned to normal levels in 24–48 h. GM‐CSF also increased myelopoiesis in the patients with myelodysplastic syndromes or following anti‐leukemic treatment. These observations suggest that this growth factor should prove a useful adjunct in the treatment of patients with malignancies and bone marrow failure. Copyright © 1990 AlphaMed Press