NUMBER OF TRANSPLANTED CD34⁺ CELLS AND BLOOD TRANSFUSION REQUIREMENTS AFTER TRANSPLANTATION IN AUTOLOGOUS PERIPHERAL BLOOD STEM CELL TRANSPLANTATION

Abstract

The effect of the number of transplanted CD34⁺ cells on post-transplant neutrophil engraftment and blood transfusion requirements in autologous peripheral blood stem cell transplantation (APBSCT) was retrospectively examined. We targeted patients who underwent APBSCT in our department from January 2006 to December 2017. APBSCT was performed 118 times in 107 cases. The median number of CD34⁺ cells was 4.24 × 10⁶/kg. Transplants with fewer than 2.0 × 10⁶/kg CD34⁺ cells occurred 11 times, but engraftment was observed in all cases. For plasma cell neoplasms, the number of days until neutrophil engraftment was significantly greater in the group transplanted with fewer than 2.5 × 10⁶/kg CD34⁺ cells than in those receiving more than 2.5 × 10⁶/kg, while transfused PC volume was significantly higher compared with the group transplanted with more than 5.0 × 10⁶/kg CD34⁺ cells. Therefore, for plasma cell neoplasms, the ideal number of CD34⁺ cells required for transplantation is 2.5 × 10⁶/kg or more. However, the risk of longer apheresis time to secure a suitable number of cells, and that of delayed engraftment of neutrophils and of PC transfusion should be carefully considered.