Comparing outcomes of matched related donor and matched unrelated donor hematopoietic cell transplants in adults with B-Cell acute lymphoblastic leukemia

BACKGROUND: Allogeneic hematopoietic cell transplantation (HCT) using human leukocyte antigen (HLA)–matched related donors (RDs) and allogeneic HCT using HLA-matched unrelated donors (URDs) produce similar outcomes for patients with acute myelogenous leukemia, whereas the donor source has been reported to be a predictor of outcomes in myelodysplastic syndrome. METHODS: Post-HCT outcomes for 1458 acute lymphoblastic leukemia patients from 2000 to 2011 were analyzed, and RD and URD transplants were compared. RESULTS: The median age was 37 years (range, 18-69 years). In the multivariate analysis, HLA 8/8 allele–matched URD recipients had similar transplant-related mortality (TRM) and all-cause mortality in comparison with RD recipients (hazard ratios [HRs], 1.16 [95% confidence interval (CI), 0.91-1.48] and 1.01 [95% CI, 0.85-1.19], respectively); 7/8 URD recipients had a greater risk of TRM and all-cause mortality in comparison with RD recipients (HRs, 1.92 [95% CI, 1.47-2.52] and 1.29 [95% CI, 1.05-1.58], respectively). The risk of TRM and all-cause mortality was also greater for 7/8 URD recipients versus 8/8 URD recipients. Compared with RD recipients, both 8/8 and 7/8 URD recipients had a lower risk of relapse (HRs, 0.77 [95% CI, 0.62-0.97] and 0.75 [95% CI, 0.56-1.00], respectively). Both 8/8 and 7/8 URD recipients had a greater risk of acute graft-versus-host disease (GVHD; HRs, 2.18 [95% CI, 1.76-2.70] and 2.65 [95% CI, 2.06-3.42], respectively) and chronic GVHD (HRs, 1.28 [95% CI, 1.06-1.55] and 1.46 [95% CI, 1.14-1.88], respectively) in comparison with RD recipients. CONCLUSIONS: In the absence of RD transplantation, 8/8 URD transplantation is a viable alternative with similar survival outcomes, whereas 7/8 URD transplantation is associated with poorer overall survival. Cancer 2017;123:3346-55.