Analysis of 462 Transplantations from Unrelated Donors Facilitated by the National Marrow Donor Program

TLDR

Allogeneic bone marrow transplantation is curative for many hematologic and metabolic diseases, yet only 25–30 % of patients have HLA‑identical siblings, prompting the 1986 creation of the National Marrow Donor Program to source unrelated donors and achieving a 52 % survival rate for congenital disorders. The program was established in 1986 to facilitate finding and procuring marrow from unrelated donors, and in its first four years 462 patients received transplants. Engraftment by 100 days occurred in 94 % of patients (8 % later had secondary graft failure), acute GVHD (grades II–IV) occurred in 64 %, chronic GVHD at one year in 55 %, two‑year disease‑free survival was 40 % for leukemia patients with good prognostic factors and 19 % for higher‑risk patients, 29 % of aplastic anemia patients were alive at two years, and myelodysplasia patients had 18 % disease‑free survival.

Abstract

Allogeneic bone marrow transplantation is curative in a substantial number of patients with hematologic cancers, marrow-failure disorders, immunodeficiency syndromes, and certain metabolic diseases. Unfortunately, only 25 to 30 percent of potential recipients have HLA-identical siblings who can act as donors. In 1986 the National Marrow Donor Program was created in the United States to facilitate the finding and procurement of suitable marrow from unrelated donors for patients lacking related donors.During the first four years of the program, 462 patients with acquired and congenital lymphohematopoietic disorders or metabolic diseases received marrow transplants from unrelated donors. The probability of engraftment by 100 days after transplantation was 94 percent, although 8 percent of patients later had secondary graft failure. The probability of grade II, III, or IV acute graft-versus-host disease was 64 percent, and the probability of chronic graft-versus-host disease at one year was 55 percent. The rate of disease-free survival at two years among patients with leukemia and good prognostic factors was 40 percent and among patients at higher risk, 19 percent. Twenty-nine percent of the patients with aplastic anemia were alive at two years, and the rate of two-year disease-free survival among patients with myelodysplasia was 18 percent. For patients with congenital immunologic or nonimmunologic disorders, the probability of survival was 52 percent.The National Marrow Donor Program has benefited a substantial number of patients in need of marrow transplants from closely HLA-matched unrelated donors and has facilitated the recruitment of unrelated donors into the donor pool and the access to suitable marrow.