Similar Outcomes of Cryopreserved Allogeneic Peripheral Stem Cell Transplants (PBSCT) Compared to Fresh Allografts

Abstract

The BMT program at Princess Margaret Hospital performed 105 transplants using cryopreserved peripheral blood stem cells (PBSC) from related allogeneic donors. The outcomes were compared with those of a historic control of 106 patients transplanted with freshly procured PBSC. The infusions were tolerated with limited toxicity related to nausea/vomiting or bradycardia, correlated with the total amount of DMSO infused. The average viability of the total nucleated cell (TNC) population after thawing was 71%. The survival of clonogenic progenitors amounted to 75% for colony-forming unit-granulocyte-macrophage (CFU-GM), 69% for burst-forming units erythroid (BFU-E), and 78% for colony-forming units granulocyte-erythrocyte-monocyte-megakaryocyte (CFU-GEMM). In contrast, colony-forming units megakaryocyte (CFU-MEG) was significantly more cryosensitive with recovery rates of 39%. The number of viable CD34 + cells transplanted was correlated with the number of transplanted viable CFU-GM ( P < .001), BFU-E ( P < .001), CFU-MEG ( P < .001), and CFU-GEMM ( P = .049), but not with the TNC dose. The number of transplanted CD34 + cells was correlated with engraftment of neutrophils ( P = .012) and platelets ( P = .013). The outcomes of cryopreseved or fresh PBSC transplants (PBSCT) with respect to engraftment of neutrophils ( P = .178) and platelets ( P = .785), lymphocyte recovery ( P = .926), acute ( P = .113), and chronic graft-versus-host disease ( P = .673), recurrence ( P = .295), nonrelapse mortality ( P = .340), and overall survival ( P = .668) were not significantly different. It is therefore reasonable to consider the option of cryopreserved allografts.