An overwhelming percentage of patients who need an unrelated bone marrow transplant will have a suitably matched, available donor on the Be The Match Registry ® , operated by the National Marrow Donor Program® (NMDP)/Be The Match® , according to a new study published yesterday in the New England Journal of Medicine.
Donors are matched to patients based on human leukocyte antigen (HLA) markers, which are inherited. Depending on the patient's race or ethnic background, the study found that 66 to 97 percent of patients will have a suitably matched and available donor on the registry. The study was led by Bioinformatics scientists at NMDP/Be The Match , through its research program CIBMTR ® (Center for International Blood and Marrow Transplant Research), in collaboration with the Medical College of Wisconsin (MCW).
"The high likelihood of being able to find a suitable match, which means seven out of eight necessary HLA markers or better, is extremely good news for patients and their physicians," said Martin Maiers, director, Bioinformatics Research at NMDP/Be The Match. "Even without a fully matched donor, transplant is often the best or only option for patients with blood cancers and other deadly diseases where non-transplant therapy offers little chance of cure."
A bone marrow or umbilical cord blood transplant can be a potentially life-saving treatment for more than 70 different diseases, including several blood cancers. Patients without a suitably matched family donor can turn to the Be The Match Registry-the world's largest and most diverse donor registry, with 11 million potential bone marrow donors and 193,000 cord blood units, and access to 22.5 million donors and 601,000 cord blood units worldwide.
Using HLA data from the Be The Match Registry, the study's authors built models based on U.S. population genetics, enabling them to predict the likelihood that a suitable adult donor or banked cord blood unit could be identified for patients in 21 race and ethnic groups.
Depending on the group, researchers found that between 81 to 99 percent of patients will have at least one matched cord blood unit. For patients who are candidates for either bone marrow or cord blood transplants, the likelihood of having a suitable match is as high as 91 to 99 percent. Additionally, the researchers found that a fully matched (i.e., eight out of eight necessary HLA markers) and available donor is available for 16 to 75 percent of patients.
"This research confirms that physicians should identify the best available donor with minimal delay. Transplant should not be postponed in anticipation of finding a perfect match," said Dr. Dennis Confer, chief medical officer, NMDP/Be The Match, associate scientific director for CIBMTR and study co-author. "Using a suitable match reflects current clinical practice. Research by CIBMTR and others supports that patients transplanted earlier in their disease have better outcomes than patients with advanced disease, regardless of the degree of the match."
Confer cautioned that while the percentage of finding an unrelated donor or cord blood unit is very high for many patients, those from diverse racial or ethnic backgrounds face greater challenges in finding a match.
"We cannot yet find a suitably matched and available donor for every patient, so we cannot slow down our efforts to expand the registry and fund more research to overcome these challenges," Confer continued. "To find a match for all patients, it is critical that those who join the registry remain committed to donate when called, and that we continue to add people to the Be The Match Registry for racial and ethnic groups of highest need."