COMPARISON OF PERIPHERAL-BLOOD STEM-CELLS MOBILIZED WITH GRANULOCYTE-COLONY-STIMULATING FACTOR WITH OR WITHOUT PRIOR STANDARD-DOSE CHEMOTHERAPY IN PATIENTS WITH MALIGNANCY

We studied the effect of granulocyte colony-stimulating factor on the magnitude of peripheral blood stem cell mobilization in patients with malignancy. The leukapheresis products mobilized with granulocyte colo ny-stimulating factor alone at a steady state (a period of full hemato poietic recovery) (group 1) were compared with those obtained after cy totoxic chemotherapy using granulocyte colony-stimulating factor (grou p 2). In group 1, six patients underwent six courses of stem cell coll ection with a median of 20 1 leukapheresis. In group 2, 10 patients un derwent 12 courses of stem cell collection with a median of 10 1 leuka pheresis. Median yields of group 1 vs. group 2 were mononuclear cells (x10(9)), 21.9 vs. 11.6; CD34(+) cells (x10(6)/l), 14.5 vs. 17.1; colo ny-forming unit for granulocyte-macrophage (/ml), 223 vs. 1193; burst- forming unit for erythroid (/ml), 29 vs. 71; colony-forming unit for e rythroid (/ml), 42 vs. 29; colony-forming unit for megakaryocyte (/ml) , 26 vs. 59. While there were no statistically significant differences in the number of CD34(+) cells between the two groups, granulocyte-ma crophage-committed progenitor cells were more enriched in the apheresi s products of group 2. The correlation between CD34(+) cells and colon y-forming unit for granulocyte-macrophage was poor. Our results demons trate that granulocyte colony-stimulating factor can mobilize a suffic ient number of progenitor cells into the peripheral blood for stem cel l transplantation with or without prior chemotherapy.