FACTORS ASSOCIATED WITH SUCCESSFUL MOBILIZATION OF PERIPHERAL-BLOOD PROGENITOR CELLS IN 200 PATIENTS WITH LYMPHOID MALIGNANCIES

Peripheral blood progenitor cells (PBPC) were mobilized and harvested in 200 patients treated for non-Hodgkin's lymphoma (n = 148), Hodgkin' s disease (n = 22) and multiple myeloma (n = 30), The variables predic ting the collection of a minimal (>2.5 x 10(6)/kg) or a high (>10 x 10 (6)/kg) CD34(+) cell count were analysed. Patients were mobilized with haemopoietic growth factors following either standard chemotherapy (n = 49) or high-dose cyclophosphamide, given alone (n = 55) or combined with high-dose VP16 (n = 86). 10 patients received haemopoietic growt h factors only. The first mobilization resulted in a PBPC harvest with enough CD34(+) cells in 179/200 patients (90%). High-dose cyclophosph amide, with or without VP16, did not mobilize a higher progenitor cell yield than standard chemotherapy, When performing multiple regression analysis in the 190 patients who received chemo therapy-containing mo bilization, only the number of previous chemotherapy regimens and the exposure to fludarabine predicted for a failure to collect a minimal P BPC count (P = 0.06 and 0.0008 respectively). The target to collect a high CD34(+) cell count was negatively associated with the number of p revious chemotherapy regimens (P = 0.002). When only non-Hodgkin's lym phoma patients were considered for multivariate analysis, loci-grade h istology with fludarabine appeared to be associated with poor PBPC cel l yield (P = 0.08 and 0.005 respectively). This data confirms that PBP C harvest should be planned early in the disease course in transplant candidates, and can be obtained after a standard course of chemotherap y.