Outcome of cord-blood transplantation from related and unrelated donors

Background: Cord-blood banks have increased the use of cord-blood transplantation in patients with hematologic disorders. We have established a registry containing information on the outcome of cord-blood transplantation. Methods: We sent questionnaires to 45 transplantation centers for information on patients receiving cord-blood transplants from 1988 to 1996. Reports on 143 transplantations, performed at 45 centers, were studied, and the responses were analyzed separately according to whether the donor was related or unrelated to the recipient. Results: Among 78 recipients of cord blood from related donors, the Kaplan-Meier estimate of survival at one year was 63 percent. Younger age, lower weight, transplants from HLA-identical donors, and cytomegalovirus-negative serologic results in the recipient were favorable prognostic factors. Graft-versus-host disease of at least grade II occurred at estimated rates of 9 percent in 60 recipients of HLA-matched cord blood and 50 percent in 18 recipients of HLA-mismatched cord blood. Neutrophil engraftment was associated with an age of less than six years (P=0.02) and a weight of less than 20 kg (P=0.02), and it occurred in 85 percent of patients receiving 37 million or more nucleated cells per kilogram of body weight. Among 65 patients who received cord blood from unrelated donors, the Kaplan-Meier estimate of survival at one year was 29 percent. Cytomegalovirus-negative serologic status in these recipients was associated with improved survival (P=0.03) and was the most important predictor of graff-versus-host disease (P=0.04). Neutrophil recovery occurred in 94 percent of the patients who received 37 million or more nucleated cells per kilogram from unrelated donors. Conclusions: Cord blood is a feasible alternative source of hematopoietic stem cells for pediatric and some adult patients with major hematologic disorders, particularly if the donor and the recipient are related.