Umbilical Cord Blood Transplantation with Reduced Intensity Regimen Effective
Researchers from the University of Minnesota have reported that adults with hematological diseases have a three year survival of almost 50% following umbilical cord blood transplantation after a reduced intensity treatment regimen. The details of this study appeared in the October 15, 2007 issue of Blood. 1
Umbilical cord blood transplants have become an integral part of the management of pediatric and adult patients with hematologic diseases who do not have a suitable related or unrelated stem cell donor. There is increasing evidence that the outcomes of patients with hematologic malignancies receiving umbilical cord blood transplants are comparable to those achieved with related and unrelated donors. One of the main advantages of cord blood transplantation is that stem cells are available without delay which is a decided advantage since many patients with malignancy worsen or die before an unrelated donor is found.
Researchers at the University of Minnesota have also suggested that adult patients have better outcomes when two separate cord blood collections are infused together because of the increased nucleated cell dose. One of the two cord blood collections is selected on the basis of being a partial rather than a full HLA match. The theory is that stem cells from the mismatched umbilical cord blood collection will contribute to initial engraftment but will ultimately be rejected by a graft versus graft reaction.
The current study included 110 patients with advanced or high-risk hematologic disease. In order to be eligible, patients in this study had to be over the age of 45 years or have significant co-morbidities that precluded the administration of a myeloablative transplant regimen. The regimen used included fludarabine, cyclophosphamide and a single low-dose of total body irradiation. Post-transplant immunosuppression was with cyclosporine and mycophenolate mofetil. The majority (85%) required two cord bloods to achieve the protocol prescribed dose of nucleated cells. Diseases treated included acute and chronic leukemias, Hodgkin’s lymphoma, non-Hodgkin’s lymphoma, multiple myeloma, myelodysplastic syndrome and aplastic anemia. Approximately a third of patients had acute leukemia in first or second remission or CML in chronic phase.
- Transplant-related mortality was 26% at three years.
- Survival was 45% at three years.
- Event-free survival was 38% at three years.
- Favorable factors for survival included absence of high-risk clinical features, better performance score and absence of severe graft-versus host disease.
- Use of two cord blood collections was also associated with improved event-free survival.
Comments: These results are probably comparable to related and unrelated donor transplants for similar patients and umbilical cord blood transplantation represents a realistic alternative source of stem cells for patients with these diseases.
Reference:
1 Brunstein CG, Barker JN, Weisdorf DJ, et al. Umbilical cord blood transplantation after myeloablative conditioning: impact on transplantation outcomes in 110 adults with hematologic disease. Blood 2007;110:3064-3070.
