Definition of Bone marrow transplant:

A bone marrow transplant is a procedure to replace damaged or destroyed bone marrow with healthy bone marrow stem cells.

Bone marrow is the soft, fatty tissue inside your bones. Stem cells are immature cells in the bone marrow that give rise to all of your blood cells.

Description:

There are three kinds of bone marrow transplants:

• Autologous bone marrow transplant: "Auto" means "self." Stem cells are removed from you before you receive high-dose chemotherapy or radiation treatment. After these treatments are done, your stems cells are put back in your body. This is called a "rescue" transplant.
• Allogeneic bone marrow transplant: "Allo" means "other." Stem cells are removed from another person, called a donor. Most times, the donor must have the same genetic makeup as the patient, so that their blood is a "match" to yours. Special blood tests are done to determine if a donor is a good match for you. A brother or sister is most likely to be a good match. However, sometimes parents, children, and other relatives may be good matches. Donors who are not related to the patient may be found through national bone marrow registries.
• Umbilical cord blood transplant: Stem cells are removed from a newborn baby's umbilical cord immediately after being born. The stem cells are stored until they are needed for a transplant. Umbilical cord blood cells are so immature, there is less of a concern that they will not match.

Before the transplant, chemotherapy, radiation, or both may be given. This may be done in two ways:

• Ablative (myeloablative) treatment: High-dose chemotherapy, radiation, or both are given to kill any cancer cells. This allows new stem cells to grow in the bone marrow.
• Reduced intensity (nonmyeloablative) treatment, also called a mini transplant: Today, some patients are getting lower doses of chemotherapy and radiation before a bone marrow transplant.

A stem cell transplant is done after chemotherapy and radiation is complete. The stem cells are delivered into your bloodstream through a tube called a central venous catheter. The process is similar to getting a blood transfusion. The stem cells travel through the blood into the bone marrow. Usually, no surgery is required.

In many cases donor stem cells can be collected directly from the person's blood. Surgery is not needed. The donor will first receive injections for a few days.

Minor surgery may be needed to collect bone marrow and stem cells from a donor. This is called a bone marrow harvest. The surgery is done under general anesthesia, which means the donor will be asleep and pain-free during the procedure. The bone marrow is removed from the hip bones.

Why the Procedure Is Performed:

A bone marrow transplant replaces bone marrow that is either not working properly or has been destroyed (ablated) by chemotherapy or radiation.

Your doctor may recommend a bone marrow transplant if you have:

• Certain cancers, such as leukemia, lymphoma, and multiple myeloma
• A disease that affects the production of bone marrow cells, such as:
  • Sickle cell anemia
  • Aplastic anemia
  • Thalassemia
  • Congenital neutropenia
  • Severe immunodeficiency syndromes
• Had chemotherapy that destroyed your bone marrow