Transplants of Umbilical-Cord Blood or Bone Marrow from Unrelated Donors in Adults with Acute Leukemia

TLDR

Cord‑blood transplants from unrelated donors have shown promise in adults, but differ from matched marrow transplants in HLA compatibility and cell dose. In a retrospective cohort of 682 adults with acute leukemia (98 cord‑blood, 584 marrow) transplanted between 1998–2002, cord‑blood recipients were younger, lighter, and had more advanced disease, with data reported to Eurocord and EBMT. Cord‑blood transplantation reduced acute GVHD risk (RR 0.57) but delayed neutrophil recovery (RR 0.49), while chronic GVHD, mortality, relapse, and leukemia‑free survival were comparable to marrow, supporting cord blood as an alternative source.

Abstract

Promising results of cord-blood transplants from unrelated donors have been reported in adults.We compared outcomes in 682 adults with acute leukemia who received a hematopoietic stem-cell transplant from an unrelated donor: 98 received cord blood and 584 received bone marrow. The transplantations were performed from 1998 through 2002 and reported to Eurocord and the European Blood and Marrow Transplant Group.Recipients of cord blood were younger than recipients of bone marrow (median, 24.5 vs. 32 years of age; P<0.001), weighed less (median, 58 vs. 68 kg; P<0.001), and had more advanced disease at the time of transplantation (52 percent vs. 33 percent, P<0.001). All marrow transplants were HLA matched, whereas 94 percent of cord-blood grafts were HLA mismatched (P<0.001). The median number of nucleated cells that were infused was 0.23x10(8) per kilogram of the recipient's body weight for cord blood and 2.9x10(8) per kilogram for bone marrow (P<0.001). Multivariate analysis showed lower risks of grade II, III, or IV acute graft-versus-host disease (GVHD) after cord-blood transplantation (relative risk, 0.57; 95 percent confidence interval, 0.37 to 0.87; P=0.01), but neutrophil recovery was significantly delayed (relative risk, 0.49; 95 percent confidence interval, 0.41 to 0.58; P<0.001). The incidence of chronic GVHD, transplantation-related mortality, relapse rate, and leukemia-free survival were not significantly different in the two groups.Cord blood from an unrelated donor is an alternative source of hematopoietic stem cells for adults with acute leukemia who lack an HLA-matched bone marrow donor.