MOBILIZATION OF PERIPHERAL-BLOOD PROGENITOR CELLS BY HIGH-DOSE ARA-C,VP-16 AND RECOMBINANT HUMAN GRANULOCYTE-COLONY-STIMULATING FACTOR - FACTORS AFFECTING PROGENITOR-CELL YIELDS

Forty seven patients with hematological malignancies were treated with high doses of cytosine arabinoside (Ara C; 12 g/m(2)) and etoposide ( VP-16), followed by recombinant human granulocyte colony-stimulating f actor (rhG-CSF; 50 mu g/m(2)). Peripheral blood progenitor cells (PBPC ) were collected during rapid leukocyte recovery using a CS-3000 blood cell separator. A blood volume of 9 liters was processed in each aphe resis, with 162 apheresis procedures performed. The mean numbers of mo nonuclear cells (MNC) and colony-forming unit granulocyte-macrophage ( CFU-GM) harvested per apheresis were 4.4 x 10(8)/kg and 142.5 x 10(4)/ kg, respectively. A sufficient number of CFU-GM for engraftment (>30 x 10(4)/kg) could be harvested by a single apheresis in 35 of 47 patien ts (74%). Various factors that influence the collection of progenitor cells were analyzed by univariate and multivariate analyses. The numbe r and duration of previous chemotherapy cycles were the most significa nt factors affecting CFU-GM yield. In patients with malignant lymphoma , age also had an influence in addition to these two factors. MNC harv ested had an impact on CFU-GM yields by univariate analysis. These obs ervations suggest that high-dose Ara C plus VP-16 followed by G-CSF is an effective regimen for harvesting PBPC. PBPC should be collected in the early stage of first-line chemotherapy.