Mismatched Cord Blood Can Save Kids
Cord Blood Transplant as Good as Bone Marrow Transplant for Leukemia
WebMD News Archive
Cord Blood and Child Leukemia
Wagner and colleagues studied children treated for leukemia before their
16th birthday. Treatment means using chemotherapy to kill off their white blood
cells. To replenish these crucial immune system cells, 282 of the kids got bone
marrow transplants and 503 got cord blood transplants.
Both bone marrow and cord blood contain blood stem cells capable of
replacing the cells lost to chemotherapy. But the transplants only take if the
donor's tissues carry nearly all the same "self" markers -- called HLA
-- as the patient's tissues.
The worse the HLA match, the greater the chance the transplanted cells will
see the patient's body as "foreign" and attack it.
But earlier studies suggested that cord blood cells didn't have to be a
perfect match. Of the six crucial HLA markers, cord blood seemed to work if one
or even two HLA markers were mismatched.
Wagner and colleagues looked at how many kids remained leukemia-free after
five years -- a milepost that usually means the patient is cured of cancer.
Sure enough, kids who got cord blood transplants mismatched for one or two
HLA markers did as well as kids who got matched bone-marrow transplants. And
kids who got perfectly matched cord blood transplants seemed to do even better
than those who got matched bone marrow transplants.
Kids with leukemia aren't the only patients who badly need bone marrow
transplants. The treatment can also save the lives of children born with
dysfunctional immune systems. Many such children, Kleiner says, can't survive a
long search for a matched marrow donor.
"No longer do we have to keep searching for that matched marrow
donor," Wagner says. "Fifteen thousand patients -- right now -- cannot
find a donor. This now gives them another option. Matching is no longer the
barrier it is with marrow donors."
Wagner says that doctors are now much better at cord blood transplants than
they were when the study began. Patients today can expect much better results
than those seen in the study, he says.
The Wagner study appears in The Lancet. In an editorial accompanying
the study, Vanderson Rocha and Eliane Gluckman of Saint Louis Hospital in
Paris, advise doctors to start their search for cord blood banks and bone
marrow registries at the same time -- and to use the one they find first.
Wagner says that his group is studying whether cord blood works as well for
older adults as it does for children.