General Information on Bone Marrow Transplants

Thousands of people, both adults and children, need bone marrow transplants each year for conditions like leukemia, lymphoma, multiple myeloma, anemia and immune system disorders. According to Be The Match Registry, 70 percent of those who need bone marrow transplants do not have a match within their own families. Whether you are considering becoming a bone marrow donor or are a patient facing a bone marrow transplant in your future, learning more about the process will help you make informed decisions.

Bone Marrow Defined

• Inside of your bones, you have soft, fatty tissue known as bone barrow. This tissue is responsible for blood production. It contains stem cells, which are immature cells that have the ability to grow into other cells in the body. Many of the stem cells in the bone marrow grow into blood cells, including red blood cells, white blood cells and platelets. Bone marrow transplants involve the transplantation of these stem cells from a healthy patient to one whose bone marrow has been destroyed through cancer treatment or is not working properly due to another disease.

Types

• Patients may undergo one of three types of bone marrow transplants. Autologous bone marrow transplants involve the harvesting of a patient's own stem cells prior to radiation therapy or chemotherapy, and then transplanting them back into the patient after the procedure. An allogeneic bone marrow transplant is a transplant that occurs from a donor to a sick patient. An umbilical cord blood transplant involves transplanting stored umbilical cord blood that was harvested just after the birth of a baby into a patient in need of marrow.

Donor Selection

• Patients who cannot use their own stem cells must receive marrow from a donor. Bone marrow donors must have the same genetic typing as the patient, which means their blood matches the patient's blood. The best candidates for bone marrow transplants are a patient's full siblings. When siblings or other close family members are not a match or are not available to donate, a patient must search a list of registered donors for a match. Be The Match, one of the leading bone marrow donor registries, indicates that doctors determine matches based on human leukocyte antigen (HLA) tissue type matching, which involves a simple blood test.

Harvesting Procedure

• Bone marrow transplants begin with the harvesting procedure. During this procedure, the physician will harvest bone marrow from the donor using a needle inserted into the cavity of the rear hip bone. One to two qts. of bone marrow are harvested, which is about 2 percent of an adult's bone marrow. This is replaced by the donor's body, causing the donor no lasting problems. Donors may experience slight pain at the harvest site, but donating bone marrow poses few other risks. The morrow is then frozen until the transplant procedure.

Preparation

• Patients receiving a bone marrow transplant will prepare for the transplant with radiation or chemotherapy treatment. This destroys the patient's existing bone marrow to make room for the donated marrow. Radiation or chemotherapy treatment weakens the patient's immune system, so patients must take care to avoid exposure to people who are ill during this time. Patients will also receive a central venous line, a catheter inserted into the vein above the patient's heart, which makes it easier for medical personnel to administer medication and get blood samples throughout the transplant process.

The Transplant and After

• One to two days after receiving chemotherapy or radiation, the patient will receive the transplant. A bone marrow transplant is not a surgical procedure, but rather the patient will receive the bone marrow through an IV like any other blood product. The transplant occurs in the patient's room. The two to four weeks after the transplant are the most dangerous for the patient, as the body must have time to engraft the new marrow and begin producing blood cells. Patients are carefully monitored during this time for any infections, as they have lowered immunities. Platelet transfusions are common during the engrafting period.

Risks

• Bone marrow transplantation is a life-saving medical procedure, but it is not without its risks. Infection is the most dangerous risk, as patients do not have the immunities to fight infections while the new marrow is grafting. Internal bleeding is another potentially deadly risk. Sometimes grafts do not take, and a few patients experience graft versus host disease, which occurs when the donor's cells attack the patient's body. Other risks include pain, anemia, digestive problems, cataracts, early menopause, delayed growth in children, and damage to the lungs, heart, liver or kidneys.