Stem cell transplantation for leukemia

A stem cell transplant can be used to restore healthy bone marrow in patients with leukemia. Stem cells help stimulate new bone marrow growth and restore the immune system.

The two main types of stem cell transplants are:

Autologous stem cell transplant: In this procedure, stem cells are collected from the patient's blood, harvested, frozen and stored until needed, then infused back into the patient after he/she has received high dose chemotherapy and/or radiation therapy to destroy the cancer cells.

Allogeneic stem cell transplant: In this type of transplant, stem cells are taken from a matching donor. To determine if a donor’s stem cells are the right match, the patient undergoes a human leukocyte antigens (HLA) test. In an HLA test, we compare the patient’s blood and tissue type with blood samples from the donor.

Before a stem cell transplant for leukemia, you will undergo a conditioning regimen, which involves intensive treatment to destroy as many leukemia cells as possible. You may receive high doses of chemotherapy and, in some cases, radiation therapy. You may also receive reduced-intensity conditioning (sometimes referred to as a mini-allogeneic transplant), which uses lower, less toxic doses of chemotherapy and/or total body irradiation before the transplant.

Once this preparative regimen is complete, you are ready to undergo the transplant. Much like a blood transfusion, you’ll receive the stem cells intravenously. The procedure takes about an hour. After entering the bloodstream, the stem cells travel to the bone marrow and start to make new blood cells in a process known as engraftment.

In the months following the transplant, your care team will monitor your blood counts. You may need transfusions of red blood cells and platelets. Sometimes, the intensive treatments you receive before the stem cell transplantation for leukemia can cause side effects, such as infection. In this case, your doctor may administer IV antibiotics.

An advantage of an allogeneic transplant is that the stem cells come from a healthy donor with no malignant cells. However, since it can be difficult to find a matching donor, an autologous transplant is usually more common. Also, if you had an allogeneic stem cell transplant, your doctor may prescribe certain drugs to reduce the risk of graft-versus-host-disease (GVHD), a condition where the donated cells attack the patient's tissues.

Recovery from a leukemia stem cell transplant may take several months. Your hematologic oncology team will work together with the rest of your care team to support you throughout the process.

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