SAN DIEGO, Calif--Investigators have demonstrated that umbilical
cord blood contains cells capable of instituting long-term, donor-derived
hematopoiesis--with a very low probability of producing graft-versus-host
disease (GVHD), John E. Wagner, MD, said at a conference sponsored
by the University of California, San Diego Cancer Center and the
UCSD School of Medicine.
Human umbilical cord and placental blood is known to contain hematopoietic
progenitor cells at a frequency that is equal to or greater than
that in adult bone marrow. This led to investigations of its use
to help "remedy, or at least reduce, some of the risks associated
with allogeneic bone marrow transplantation (BMT)," said
Dr. Wagner, associate professor of pediatrics, University of Minnesota
School of Medicine, Minneapolis.
The first successful umbilical cord blood transplant from a sibling
donor was performed in 1988, and since that time, 43 additional
transplants have been performed worldwide and reported to the
International Cord Blood Transplant Registry. These patients had
a variety of malignant (primarily childhood leukemias) and nonmalignant
disorders. Their median age was 4 years, and median weight, 18.6
The children received high-dose chemoradiation and were infused
with umbilical cord blood from sibling donors. The majority of
these transplants (77%) were HLA-identical grafts.
Engraftment Same as With BMT
Evidence of hematopoietic recovery was seen in 85% of those transplanted.
"The range of hematopoietic recovery was exactly the same
range as you would see with BMT; however, the median time to recovery
was 22.5 days, which may be somewhat prolonged as compared with
BMT," Dr. Wagner said.
With a median follow-up of 1.6 years, the overall survival of
the group was 70%, he said. Event-free survival was 49% for those
patients with malignant diseases, and 76% for those with nonmalignant
conditions, although some relapses did occur over time.