Monday, April 28, 2014

Bone Marrow Transplants A Lot Safer Now

Sandra Haber, a 65-year-old psychologist in Brooklyn, wants everyone to know how easy it is now to donate bone marrow.

Hers was failing. She was anemic, bled easily and had little resistance to infection. As her condition progressed toward leukemia, doctors at Memorial Sloan-Kettering Cancer Center urged her to get a bone-marrow transplant. Fortunately, there was a donor: Testing showed that a sister living in New Mexico was a perfect match.

But at first Haber's sister was hesitant, fearful of the general anesthesia, painful withdrawal of marrow from a hip bone and difficult recovery she thought was involved. Yet she came to New York for further tests and learned that the process was simple and safe: basically a lengthy blood donation after a week of daily injections to spur her own bone marrow to produce an oversupply of stem cells.

About 90 percent of bone marrow "transplants" are now done this way, most often with stem cells from a matched donor's blood, sometimes from a baby's umbilical cord and placenta or the patient's own stem cells. After the recipient's own dysfunctional marrow is destroyed by intensive chemotherapy and sometimes total body radiation, the donated stem cells are infused into the recipient's blood through a special intravenous line, called a central line. The cells find their way to bone marrow, where they gradually restore the recipient's ability to produce red and white blood cells and platelets.

"A stem cell transplant is not a walk in the park," Haber said. "It's more like a marathon than a sprint, and the healing process is long and not linear."

It typically takes six months to a year to regain full blood cell production and immune function, during which special precautions are essential.

But when a life is saved, the challenges are worth it, recipients say. Haber said her weeks in the hospital in relative isolation were not especially difficult. She described the fatigue afterward as more of a hardship, but that, too, abated as she has gradually regained her former energy.

Now Haber wonders why a sign in her hospital still reads "Bone Marrow Transplant Unit," when marrow donation is a rarity and the thought of it may scare off potential donors.

Many in need of healthy bone marrow die before a good match can be found. Haber thinks if the language changed, far more people from diverse ethnic and racial groups might be willing to join the American Bone Marrow Donor Registry -- whose name perhaps should also be changed.

Donors must be 18 to 60 and healthy. Registration involves just a cheek swab from which the donor's tissue type is analyzed and stored in a national database.

When someone who needs new bone marrow has no close match among eligible relatives, doctors check the registry for a matching volunteer elsewhere. The need is especially great for patients who are African-American, Asian or of mixed ethnic or racial backgrounds.

A match is determined by checking proteins called HLA antigens present on cells from the donor and recipient. As with other traits, people inherit the genes that determine these antigens from each parent; the more genetically distant the parents, the less common the mix of antigens is likely to be. Without a very close match, the donor's cells are likely to attack the recipient's tissues, a potentially fatal complication called graft-versus-host disease.

Stem cell transplants can help people whose bone marrow is diseased or dysfunctional and unable to produce the red blood cells that carry oxygen, white blood cells that fight infections, or platelets that enable the blood to clot. Such conditions include cancers like leukemia, certain lymphomas, multiple myeloma and aplastic anemia; inherited disorders like sickle cell anemia and thalassemia; and severe immune deficiency disorders in newborns.

For cancer patients, a stem cell transplant offers an additional benefit: The new blood cells can attack errant cancer cells that may have survived the original chemotherapy.

Stem cell transplants are expensive, $100,000 to $200,000.

Prospective patients are urged to check with their insurance carriers before embarking on the process.

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