Impact of autologous blood transfusion after bone marrow harvest on unrelated donor's health and outcome: a CIBMTR analysis.

Pre-harvest autologous blood collection from bone marrow (BM) donors is performed to meet potential post-operative transfusion needs. This study examines the impact of autologous blood transfusion on BM donor's health and safety. The study included first-time unrelated BM donors from the United States whose BM harvest was facilitated by the National Marrow Donor Program (NMDP) centers between 2006 and 2017. Examination of 7024 BM donors revealed that 60% received at least one unit of autologous blood. The donors who received autologous blood were older, had lower hemoglobin pre-harvest, underwent longer duration of anesthesia, and higher volume BM harvest. Only donors who underwent high-volume BM harvest, defined as a BM harvest volume >27% of donor's blood volume, benefited from autologous transfusion. After a high-volume BM harvest, autologous blood transfusion was shown to decrease grade 2 to 4 collection-associated toxicities within 48 h of BM donation (p = 0.010) and shorten the time to donor-reported "complete" recovery from donation-associated symptoms (p < 0.001). Therefore, autologous transfusion could be avoided as support of marrow donation in the majority of unrelated BM donors and should be limited to cases where the planned BM harvest volume is expected to exceed 27% of donor's blood volume.

GRFS and CRFS in alternative donor hematopoietic cell transplantation for pediatric patients with acute leukemia.

We report graft-versus-host disease (GVHD)-free relapse-free survival (GRFS) (a composite end point of survival without grade III-IV acute GVHD [aGVHD], systemic therapy-requiring chronic GVHD [cGVHD], or relapse) and cGVHD-free relapse-free survival (CRFS) among pediatric patients with acute leukemia (n = 1613) who underwent transplantation with 1 antigen-mismatched (7/8) bone marrow (BM; n = 172) or umbilical cord blood (UCB; n = 1441). Multivariate analysis was performed using Cox proportional hazards models. To account for multiple testing, P < .01 for the donor/graft variable was considered statistically significant. Clinical characteristics were similar between UCB and 7/8 BM recipients, because most had acute lymphoblastic leukemia (62%), 64% received total body irradiation-based conditioning, and 60% received anti-thymocyte globulin or alemtuzumab. Methotrexate-based GVHD prophylaxis was more common with 7/8 BM (79%) than with UCB (15%), in which mycophenolate mofetil was commonly used. The univariate estimates of GRFS and CRFS were 22% (95% confidence interval [CI], 16-29) and 27% (95% CI, 20-34), respectively, with 7/8 BM and 33% (95% CI, 31-36) and 38% (95% CI, 35-40), respectively, with UCB (P < .001). In multivariate analysis, 7/8 BM vs UCB had similar GRFS (hazard ratio [HR], 1.12; 95% CI, 0.87-1.45; P = .39), CRFS (HR, 1.06; 95% CI, 0.82-1.38; P = .66), overall survival (HR, 1.07; 95% CI, 0.80-1.44; P = .66), and relapse (HR, 1.44; 95% CI, 1.03-2.02; P = .03). However, the 7/8 BM group had a significantly higher risk for grade III-IV aGVHD (HR, 1.70; 95% CI, 1.16-2.48; P = .006) compared with the UCB group. UCB and 7/8 BM groups had similar outcomes, as measured by GRFS and CRFS. However, given the higher risk for grade III-IV aGVHD, UCB might be preferred for patients lacking matched donors.