Blood from umbilical cords -- a byproduct of normal childbirth -- is a good source of hematopoietic progenitor cells (HPCs), the type of stem cells also found in bone marrow that give rise to various kinds of blood cells. Transplants of these stem cells have saved the lives of roughly 20,000 Americans with leukemia, lymphoma, sickle cell anemia, and several other illnesses in recent years, the report notes. But thousands of patients who might benefit from a transplant die every year waiting for a match. Although 22 public banks have been established in the United States to collect, store, and distribute donated cord blood containing these cells, these banks operate without any centralized coordination, noted the committee that wrote the report.
"The lack of centralized organization, universal quality standards, and uniform matching mechanisms makes it more difficult than it has to be for physicians to provide patients with suitable cells in a timely way," said Kristine Gebbie, associate professor of nursing and director of the Center for Health Policy and Doctoral Studies Columbia University, New York City, and chair of the committee that wrote the report. "Moreover, there simply aren't enough units of cord blood available now to meet the needs of the roughly 11,700 Americans who could benefit from a transplant of these cells every year. The structure we are recommending for a national cord blood banking program would assure that patients receive high-quality therapeutic cells in the most timely, ethical, and cost-effective manner possible."
Three-quarters of the patients who require a transplant of HPCs do not have a relative whose cells would be a suitable match and must turn to public bone marrow donor registries or umbilical cord blood banks for donated cells. By increasing the size and quality of the cord blood inventory, nearly 90 percent of all patients who need a transplant should be able to find a suitable match from either cord blood banks or marrow donor registries, the report says.
The new National Cord Blood Policy Board should be established at the level of the office of the DHHS secretary to ensure that it is distanced from the day-to-day concerns of other parts of the department responsible for managing relationships with and funding for bone marrow donor programs and cord blood programs, the committee urged. The board should routinely review the results of cord blood stem cell transplants and guide DHHS and the cord blood banking program on procedures and standards for banking and allocation and on any changes to the inventory of cord blood units.
Decisions about which source of HPCs to tap must be made on a case-by-case basis and driven by the patient's needs, the report notes. To that end, the board should actively encourage collaboration between marrow donor registries and cord blood banks, as well as support cord blood banking's emergence as a transplant option.
Although the National Marrow Donor Program (NMDP) and other organizations have developed several of the components necessary to manage daily coordination of banking and allocation on a large scale, no organization currently has all the necessary capabilities to serve as the Cord Blood Coordinating Center, the committee concluded. HRSA officials should use a competitive process to solicit proposals and identify an organization to take on this function. NMDP and other organizations would have an opportunity to present plans for ensuring that all the necessary elements are in place to link participating transplant centers and cord blood banks; establish standards for cord blood storage and matching; and make sure that data on the results of transplants are available for decision-making and quality assurance. Although the new center would coordinate these various activities, it need not assume all of these functions itself, the report says.
The majority of funding available for the national cord blood bank program should be targeted to expanding the inventories of participating banks. Based on the current estimate that 50,000 useable units of cord blood are now available through public banks and the NMDP, the committee projects a need for at least 100,000 more high-quality units. The larger the inventory, the greater the likelihood that a patient will be matched to a suitable unit and receive an optimal dose of cells, although the costs of collecting and storing cord blood also must be considered. The point at which the costs of banking cord blood exceed the benefits for the patient population is 200,000 units, according to an economic analysis conducted for the study.
Cord blood banks should strive to provide units with a high-enough concentration of stem cells to make up for imperfect matches between donor and recipient -- a frequent occurrence, the report notes. The more closely surface markers on donated cells match those on a patient's own cells, the less likely that the patient's body will reject the transplant. In many cases, a mismatch of one or two degrees is the best that can be found in public banks. Patients for whom an ideal match cannot be located should receive units that contain at least 2.5 x 107 cells per kilogram of body weight, the report says. When perfect matches can be found, cell concentration is less important.
For many racial and ethnic minority patients, it is difficult or impossible to find suitable matches because many cord blood collections are not ethnically and racially diverse. The committee's own survey determined that 62 percent of the current total inventory in the United States came from white donors, 15 percent from Hispanics, 7 percent from African-Americans, 5 percent from Asians, 5 percent from mixed race donors, and 1 percent from American Indians. However, individual cord blood banks have achieved greater diversity through geographically targeted collection efforts and other means, the report notes.
This study was sponsored by the Health Resources and Services Administration. The Institute of Medicine is a private, nonprofit institution that provides health policy advice under a congressional charter granted to the National Academy of Sciences. A committee roster follows.
A pre-publication version of CORD BLOOD: ESTABLISHING A NATIONAL HEMATOPOIETIC STEM CELL BANK PROGRAM is available from the National Academies Press; tel. (202) 334-3313 or 1-800-624-6242 or on the Internet at HTTP://WWW.NAP.EDU. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above).
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