FACTORS AFFECTING BOTH PERIPHERAL-BLOOD PROGENITOR-CELL MOBILIZATION AND HEMATOPOIETIC RECOVERY FOLLOWING AUTOLOGOUS BLOOD PROGENITOR-CELL TRANSPLANTATION IN MULTIPLE-MYELOMA PATIENTS - A MONOCENTRIC STUDY

The aim of the study was to analyze the factors influencing peripheral blood progenitor cell (PBPC) collection after high-dose cyclophospham ide (HDCYC) (7 g/m(2)) and hematopoietic recovery after autologous tra nsplantation of HDCYC-mobilized PBPC (ABPCT) in 116 patients with aggr essive multiple myeloma (MM). Following HDCYC 74 patients received hem atopoietic growth factors (HGF), either G-CSF (n = 19) or GM-CSF (n = 55). All the patients were subsequently planned to undergo ABPCT. PBPC collection was possible for 106 patients. The most important prognost ic factor for collection of more than 25 x 10(4) CFU-GM cells/kg and 2 x 10(6) CD34(+) cells/kg was the use of HGF (P = 0.002 and 0.009, res pectively). Previous use of an alkylating agent, response to treatment before HDCYC, and interval between diagnosis and HDCYC were also sign ificant factors (P = 0.004, 0.025 and 0.001, respectively). The number of CFU-GM cells infused was the most important parameter for rapid an d complete hematological recovery after ABPCT (P < 0.0001). Thus the u se of HGF post-HDCYC is the major factor which, associated with reduce d time between diagnosis and HDCYC and the use of an alkylating agent, could increase the numbers of hematopoietic progenitors collected, an d subsequently improve hematopoietic recovery following ABPCT in MM pa tients.