Correlation between Progenitor Cell Dose and the Rate of Engraftment in Autologous Peripheral Blood Stem Cell Transplantation and Allogeneic Bone Marrow Transplantation / 대한수혈학회지

ABSTRACT

BACKGROUND: Bone marrow transplantation (BMT) or peripheral blood stem cell transplantation (PBSCT) following high dose chemotherapy has been an important therapeutic option for patients with hematologic malignancies or some solid tumors. The number of progenitor cells in the collection products has been used to determine the optimum time to stop the collections and to predict the hematopoietic engraftment after transplantation. In this study, we investigated the relationship between end-product cell counts measured by different methods and the influence of the infused cell dose on the engraftment rate. METHODS: Twenty five patients receiving autologous PBSCT and 25 patients receiving allogeneic BMT were studied. The number of total nucleated cells (TNC), of mononuclear cells (MNC), of CD34+ cells, and of CFU-GM (colony-forming unit-granulocyte monocyte) colonies were measured in each collection product. The number of days required to achieve an absolute neutrophil count (ANC) of 0.5x109/L with TNC count of 1.0x109/L and platelet count of 20x109/L without transfusions was taken as an arbitrary measure of the engraftment rate. RESLUTS: A close correlation between CD34+ cells/kg and CFU-GM/kg was observed in both collection products (p<0.05). However, MNC/kg also showed significant correlations with CD34+ cells/kg and CFU-GM/kg in allogeneic bone marrow collection products (p<0.05). The CFU-GM amount in the PBSC products was greater than that in the bone marrow collection products (p<0.05). Time to engraftment was a median of 14 (range 9-50) days in autologous PBSCT group, but 29 (range 17-57) days in allogeneic BMT group. In autologous PBSCT, infused CD34+ cells/kg and CFU-GM/kg correlated significantly with ANC recovery (p<0.05). CONCLUSIONS: The number of CD34+ cells was correlated with that of CFU-GM in the collection products, and the infused cell doses showed positive relation to the engraftment rate in autologous PBSCT. These findings suggest that measurement of CD34+ cell counts alone would be a sufficient parameter to predict the engraftment rate in autologous PBSCT.