Umbilical Cord Transplantation Effective Treatment

OncoEd, November 14, 2007

Following umbilical cord blood transplantation after a reduced intensity treatment regimen, adults with hematological diseases have a three year survival rate of almost 50% according to researchers from the University of Minnesota. The journal Blood1 has published the details of the study in their October 15th, 2007, issue.

For adult and pediatric patients with hematologic diseases who do not have a suitable related or unrelated stem cell donor, umbilical cord blood transplants have become and integral part of the management. In patients with hematological malignancies, treatment outcomes from unrelated and related donors are comparable to those patients receiving umbilical cord blood transplants according to increasing research evidence. Since many patients with malignancy worsen or die before an unrelated donor is found, a major and decided advantage of cord blood transplantation is that stem cells are available without delay.

Because of the increased nucleated cell dose, when two separate cord blood collections are infused together, adult patients have better outcome according to scientists at the University of Minnesota. On the basis of being a partial rather than a full HLA match, one of the two cord blood collections is selected. Ultimately, graft versus graft reaction would reject stem cells from the mismatched umbilical cord blood collection, but the theory is that they will contribute to initial engraftment none the less.

110 patients with high-risk or advanced hematological disease were enrolled in the study. Eligibility requirements for the study included a minimum age of 45, or significant co-morbidities that precluded the administration of a myeloablative transplant regimen. The regimen used included a single low-dose of total body irradiation, cyclophosphamide, and fludarabine. Mycophenolate mofetil and cyclosporine was used for post-transplant immunosuppression. In order to achieve the protocol prescribed dose of nucleated cells, the majority of patients (85%) required two cord bloods.

Aplastic anemia, non-Hodgkin's lymphoma, acute and chronic leukemias, myelodysplastic syndrome, Hodgkin’s lymphoma, and multiple myeloma were among the diseases treated. CML in chronic phase or acute leukemia in first or second remission afflicted approximately a third of the patients.

-- Improved event-free survival was observed with the use of two cord blood collections.
-- At three years, event-free survival was 38%.
-- At three years, transplant-related mortality was 26%.
-- At three years, survival was 45%.
-- The absence of severe graft-versus host disease, better performance scores, and the absence of high-risk clinical features were favorable observations.

Comments: Umbilical cord blood transplantation represents a realistic alternative source of stem cells for patients with these diseases since the results are probably comparable to related and unrelated donor transplants for similar patients.