The Wait for a Match
Many patients in urgent need of bone marrow or stem cell transplants are facing uncertainty.
By Karen Patterson
Photo by Todd Sumlin / The Charlotte Observer
Manasvi Koul entered the complicated world of cancer care in September 2005, just shy of her 13th birthday. Four cycles of intensive inpatient chemotherapy later, her stage II Hodgkin lymphoma was in remission. But not for long. Just months later, tests showed that her cancer had come surging back.
Koul’s doctors started her on more chemotherapy and began making preparations for a bone marrow transplant, also called a stem cell transplant, from a healthy donor. Although chemotherapy or radiation can help save a patient from her cancer, this type of transplant—which replaces damaged stem cells with another person’s healthy ones—can rescue her from the ravages that radiation or high-dose chemo may have inflicted on her bone marrow. Donor stem cells can replenish the patient’s blood cells and platelets, and help restore the body’s disease-fighting immune system.
First, though, Koul’s medical team needed to find a donor. Because Koul is Asian Indian and tissue types are inherited, the donor would most likely need to be someone else of Asian Indian heritage. And the likelihood that a doctor can find a match depends significantly on the patient’s race and ethnicity. Whites have a 93 percent chance of matching with a donor in Be the Match, the U.S. registry managed by the Minneapolis-based National Marrow Donor Program. In contrast, for American Indians and Alaska natives the odds are 82 percent; for Asians and Pacific Islanders they are about 73 percent; for Hispanics 72 percent, and for blacks just 66 percent.
For Koul, the odds were especially tough because her parents come from very different regions of India, a nation with numerous localized subethnicities. “It’s hard to find Indian people, period,” says Koul. “There’s so few of them who know how easy it is to save a life with bone marrow donation.”
Stem cell transplants are potentially life-saving treatment options for more than 70 diseases, including leukemia, lymphoma and marrow-failure diseases like myelodysplastic syndrome, according to Willis Navarro, a hematologist-oncologist and the medical director of transplant medical services for the National Marrow Donor Program. Outcomes can vary significantly by disease and be influenced by factors including how ill a patient is at the time of transplant.
Manasvi Koul, seen here with her family, was 12 when she was diagnosed with Hodgkin lymphoma. | Photo courtesy of the Koul Family
Donor stem cells can be extracted from bone marrow or a donor’s circulating blood or even umbilical cord blood. (See "From the Youngest Donors.") “For children, marrow is often the first choice,” says Navarro, noting that research has shown that it results in fewer complications than stem cells from circulating blood (known as peripheral blood stem cells, or PBSCs). Marrow and PBSCs seem to work equally well in adults, but PBSCs implant more quickly, shortening hospital time, he says.
The U.S. registry began in 1987 with a list of 10,000 volunteers. Today, Be the Match includes 9 million potential U.S. donors, ages 18 to 60, as well as about 185,000 units of umbilical cord blood, according to the National Marrow Donor Program. The registry facilitated more than 5,200 transplants in 2010—a number that increased on average by 15 percent annually over the last five years, Navarro says.
To find donor-patient matches, tissue testing focuses on human leukocyte antigens (HLAs), proteins that sit on the surface of cells. The antigens represent a person’s “genetic identity,” explains Navarro. Currently, he says, doctors consider at least four pairs of antigens, or eight total—the antigens are called A, B, C and DR—when looking for a match. (Each pair encompasses an antigen from the person’s mother and another from the father.) The National Marrow Donor Program advises a full match between patient and donor of all eight antigens when possible, although a lesser match might be used. Recently, doctors began looking at additional antigens to provide even closer matches, Navarro says.
In the spring of 2006, as doctors launched the search for a match for Koul and administered chemotherapy in preparation for a transplant, her cancer continued to progress. Because a match could not be found, her own stem cells were extracted and she underwent even more arduous chemotherapy. That July, doctors proceeded with an autologous transplant, which reimplants a patient’s own stem cells.
An autologous transplant eliminates the chance of transplant rejection—an immune response to a donor’s cells that’s known as graft-versus-host disease. But autologous transplants also don’t attack the cancer immunologically, like transplants from donors can, explains Navarro. “Some diseases are intrinsically resistant to chemotherapy and require the powerful immune effects against the disease called graft-versus-disease effect, in which the diseased cells are destroyed by the transplanted donor immune system.”
An autologous transplant also poses a risk that gnawed at Koul throughout her weeks in isolation awaiting her transplanted cells: that some cancer cells might have been harvested along with the stem cells and would be reintroduced.
That fear stuck with Koul for years, and eventually she decided to take action against the problem that caused her and other patients so much uncertainty and distress. On her 16th birthday in October 2008—just months after she had a PET scan showing no evidence of cancer—Koul launched the LIVEbeyond Foundation, an effort to create awareness, especially among minority groups, of the need for bone marrow and stem cell donors.