AUGUST 3, 2010
More than 3,000 people have signed up to be potential bone-marrow donors since word spread that 11-year-old Shannon Tavarez, one of the child stars of "The Lion King" on Broadway, needed a transplant to combat her acute myelogenous leukemia.
Hundreds more have joined bone-marrow registries in hopes of helping 22-year-old Mandi Schwartz, a Yale hockey player, 12-year-old Esther Persaud or 6-month-old Sophia Lopez, all of whom are battling leukemia.
If you're considering joining them, here's what you should know: signing up is simple, but a serious commitment. Donating is relatively painless, contrary to popular belief. And if the transplant succeeds, the results are astonishing.
A small amount of donated bone marrow—about 5% of the donor's total—can not only replenish a leukemia patient's diseased supply. The donated cells also seek out and destroy any remaining cancer cells and then keep growing, converting the recipient's blood type into the donor's type for the rest of his or her life.
The donor and the recipient must be a close genetic match, based on human leukocyte antigens (HLAs), which reflect parts of the immune system passed down from ancestors. Each of a patient's siblings has a 25% chance of being a compatible donor. In about 70% of cases, there is no one in the family who is a match, so patients and their doctors must turn to big international registries in hopes of finding someone who is. The Be the Match registry is the largest in the U.S., with more than 8 million samples. It links to other registries in the U.S. and overseas for a total of nearly 15 million possibilities.
For patients whose ancestors are Caucasians from northern Europe, Japanese and other areas that stayed homogenous for millennia, the chance of finding a close genetic match is more than 90%. It's only about 60% for patients with African, Hispanic or South Asian ancestors, since those groups are far more varied.
The odds are longer still for people of mixed racial backgrounds, like Broadway's Shannon Tavarese, who is half African-American and half Hispanic.
"That's why we need people of every race and mixture to join the registry," says Jeffrey Chell, chief executive officer of the National Marrow Donor Program, the nonprofit organization that runs the Be the Match Registry.
Signing Up
Joining a registry requires only a cheek swab and a health questionnaire. You must be between 18 to 55 years old and free of cancer, heart disease, hepatitis, epilepsy, HIV and other diseases. You can sign up at a local donor center or bone-marrow drive—many organizations sponsor them—or request a kit at www.marrow.org.
Once you join a registry, you are on it until you reach age 61, or ask to be removed.
If your cells are a match for a patient, you'll be asked to undergo tests to further assess your health and compatibility. There's no cost to the donor and travel expenses are reimbursed; but the tests and donation can be time-consuming.
These days, about 75% of bone-marrow transplants don't require actual bone-marrow. The donor's blood is circulated through a machine that filters out marrow-making cells called peripheral blood stem cells (PBSC), then the remaining blood is returned to the donor.
"It couldn't have been easier. I sat in a hospital bed for seven hours with a needle in one arm, and another needle in the other arm, and I could see the bag filling up with stem cells," says Caitlin Emma, 21, who joined a registry as a student at the University of Connecticut, and matched with a young leukemia patient last fall. "I felt a little light headed afterwards, but I went back to school the next day," she says.
Like all PBSC donors, she did have to get injections of a protein that stimulates marrow-growth daily for five days before the extraction, which causes flu-like symptoms.
So far, she only knows that the transplant was successful. There's a one-year confidentiality period in which donors and recipients are told very little about each other. After that, getting in touch is optional on both sides.
If a recipient requires traditional bone marrow, the donor is given either general or local anesthesia. Needles are inserted into the donor's pelvic bone in several spots to extract the liquid-like marrow inside. The procedure takes about two hours. The donor goes home the same day, and may feel like he's had a bad fall on the tailbone for several days.
"I was definitely sore. I spent a few days lying on the couch," says Stefanie Kienstra, who signed up at a campus blood drive at the University of Missouri in 2007, and matched a few months later with a 31-year-old man who had leukemia.
Meeting the Recipient
Once the one-year confidentiality period ended, the two started corresponding. They met for the first time in April at a gala hosted by DKMS, the New York-based donor center where Ms. Kienstra registered.
"I wouldn't be speaking to you today if Stefanie hadn't said, 'Sure, swab my cheek'," says the recipient, David Jolley of Seattle, who finished law school and took the bar exam last week.
The first potential donor for Mr. Jolley decided not to go through with the procedure at the last minute, something that happens occasionally. That's why donor registries ask that anyone who joins keep the registry informed of any changes in their health status, availability or address so they can be located quickly.
"Understand that when we call, the need might be urgent. The patient may have just a few weeks to live," Dr. Chell says.
In recent years, an additional source of bone-marrow transplants has emerged: the umbilical cords of newborn babies, typically discarded as medical waste.
Just two tablespoons of umbilical cord blood contains about one billion stem cells, which are so versatile they can be used to create bone marrow, as well as treating a variety of cancers and diseases. And they don't require as close a match between donor and recipient. Be the Match registry includes about 160,000 searchable cord blood units; patients often turn to those when no adult match can be found.
Donating a newborn's umbilical cord does not affect the mother, the baby or the delivery, but it does require some advance planning, since the cord must be preserved immediately after it is clamped and cut.
If the delivering hospital belongs to a public cord-blood program, the procedure is free. (For a list, see http://www.marrow.org/). If not, parents may still be able to donate, but may have to bear some costs themselves. Some obstetricians charge $150 for the procedure.
Donations to a public bank are anonymous. You'll never know when or if your baby's cord blood is used.
Parents can preserve their newborn's cord blood in a private bank in case the baby or another family member someday needs the cells for a bone-marrow transplant or other life-saving treatment. Researchers hope to one day use stem cells to treat Parkinson's, Alzheimer's and other devastating diseases. The initial cost to preserve cord blood is about $2,000, with about $200 a year for storage.
Write to Melinda Beck at HealthJournal@wsj.com
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