Umbilical-cord blood transplants, however, are primarily performed on children and smaller adults since the number of available progenitor cells is limited. Previously, smaller studies suggested that double-unit cord-blood transplants may be advantageous for patients. In a randomized prospective trial, researchers followed 224 patients 1 to 21 years old with hematologic cancers who were randomly assigned to receive either double-unit (n=111) or single-unit (n=113) cord-blood transplants. Baseline characteristics including degree of donor-recipient HLA-matching and disease type of both trial arms were matched. Double-unit transplant recipients had a one-year overall survival rate of 65% compared to 73% for single-unit recipients (P=0.17). No significant differences were observed for neutrophil recovery, death, relapse, or infections. Single-unit recipients, however, had improved platelet recovery and a lower risk of graft-versus-host disease.
1. Wagner JE, Jr., Eapen M, Carter S, Wang Y, Schultz KR, Wall DA, Bunin N, Delaney C, Haut P, Margolis D, Peres E, Verneris MR, Walters M, Horowitz MM, Kurtzberg J. for the Blood and Marrow Transplant Clinical Trials Network. One-unit versus two-unit cord-blood transplantation for hematologic cancers. N Engl J Med 2014;371: 1685-94.