Researchers affiliated with the Eurocord-Netcord Transplant Group have summarized the most recent results of umbilical cord blood transplants in adults and concluded that this is an acceptable source of stem cells for those patients lacking a related or unrelated donor. This retrospective analysis was presented at the 31st annual meeting of the European Group for Blood and Marrow Transplantation in Prague March 20-23, 2005.

Allogeneic stem cell transplantation is often the only curative therapy for many patients with hematologic malignancies. However, many patients lack a suitable family member or an unrelated donor. Over the past decade, there has been emerging data that suggests that umbilical cord blood is a suitable source of stem cells, as the immaturity of the stem cells leads to less rejection and less graft-versus host disease (GVHD). Early studies were restricted to children because of the relatively low numbers of nucleated and stem cells (CD34+ cells) present in a typical cord blood collection. However, more recent studies have included adults with some success and even more recently, there is evidence that two cord blood infusions are better than one in adults.

This study looked at the outcomes of 171 adult patients, primarily with leukemia, who received an allogeneic stem cell transplant using unrelated mismatched single cord blood as a source of stem cells. These patients did not have a suitable related or unrelated stem cell donor and were all transplanted after 1997. Table 1 summarizes the major findings of this analysis.

Table 1: Outcomes of Allogeneic Stem Cell Transplants with Unrelated Mismatched Donors

Outcomes were adversely affected by advanced disease status and lower stem cell doses.

Comments: This analysis provides updated information about the utility of umbilical cord blood in adults. This data suggests that umbilical cord blood transplants would be more effective if applied earlier in the disease course.

Reference: Arcese W, Rocha M, Labopin M, et al. Unrelated cord blood transplant in adults with haematologic malignancies. Bone Marrow Transplantation 2005;55 (supplement 2):S88, abstract number O413.