CD34(-) SUBSETS - COLLECTION AND ENGRAFTMENT KINETICS IN AUTOLOGOUS PERIPHERAL-BLOOD STEM-CELLS TRANSPLANTATION() CELL DOSE AND CD33()

Background and Objective. We analyzed the factors that affected the nu mber and quality of peripheral blood stem cells (PBSC) collected for t ransplant in order to establish a minimum threshold for rapid hematopo ietic recovery. Design and Methods. From January 1995 to November 1996 , a consecutive series of 67 patients, with hematologic and solid tumo rs underwent autologous PBSC transplantation. Collection of PBSC was p erformed after mobilization with granulocyte-colony stimulating factor (G-CSF) or with chemotherapy (CT) plus G-CSF. We calculated the facto rs that influenced PBSC collection, the kinetics of granulocyte and pl atelet recovery and the threshold value of CD34(+) cells for a rapid r ecovery. The data were analyzed by means of multivariate Cox regressio n model and the receiver operating characteristic (ROC) methodology. R esults. Our results showed that mobilization with chemotherapy plus G- CSF was associated with a higher yield of PBSC in comparison with mobi lization with G-CSF alone. Disease status, fewer cycles of conventiona l prior chemotherapy and absence of prior radiation therapy also influ enced the yield of PBSC. The number of CD34(+) cells, CD34(+)CD33(-) c ell subsets, the mobilization schedule, and the conditioning regimen c orrelated significantly with time to hematopoietic recovery. In the mu ltivariate analysis only the CD34(+)CD33(-) cell content and the total number of CD34(+) were related with rapid neutrophil and platelet rec overy, respectively. Use of G-CSF after transplant significantly short ened the neutrophil recovery time only in patients transplanted with s uboptimal dose of PBSC. Interpretation and Conclusions. These data sug gest the utility of quantitation of CD34(+) cells subsets to predict q uick engraftment. (C)1998, Ferrata Storti Foundation.