Types of Stem Cell Transplants & Bone Marrow Transplant
University Hospitals Offers Leading-Edge Stem Cell Transplant Options
Bone marrow is the tissue inside the bones. The blood (or hematopoietic) stem cells reside there. Stem cells are capable of generating all our blood cells, such as white cells, platelets, and red cells. At University Hospitals Seidman Cancer Center’s Stem Cell Transplant Program, our experts offer a variety of advanced stem cell therapy procedures to treat hematologic (blood) cancers such as leukemia and lymphoma.
How Stem Cell Therapy Works
The procedure used to replace defective bone marrow tissue is called bone marrow or stem cell transplant. The stem cell transplant is done after chemotherapy and/or radiation. The cells are delivered into the patient’s bloodstream through a central venous catheter (a tube in a large vein). This is actually similar to receiving a blood transfusion. After that, the blood-forming cells travel into the bone marrow space, where they will grow and start producing blood and reconstituting the immune system. This is not a surgery.
Types of Stem Cell Transplants
Stem cell transplants are named by the stem cell source. At UH, we offer both autologous transplants, which uses the patient’s own blood, and allogeneic, which uses cells from a donor.
Autologous Transplants
Autologous (self) transplants use a patient’s own blood forming cells to support higher doses of chemotherapy, radiation therapy, or both. Cells are procured before the high-dose therapy, frozen, and then administered back after the chemotherapy is completed. This approach allows intensification of the chemotherapy/radiation therapy, and the patient’s cells are used as a rescue.
Allogeneic Transplants
Allogeneic (donor) transplant uses cells from a compatible related or unrelated donor.
Sources of hematopoietic (blood) stem cells include the blood, the bone marrow and umbilical cord blood. Donor-recipient matching is done by a test called human leukocyte antigen (HLA). Brothers or sisters are frequently, but not always, a good match, while unrelated donors are procured through the Be the Match registry.
In allogeneic transplants, chemotherapy alone, or a combination of chemotherapy and radiation therapy, are given before the actual transplant. This regimen is used both to kill the diseased marrow, and to suppress the patient’s immune system in order to prevent it from rejecting the donor cells.
The preparative regimen will cause blood counts to decrease in number and frequently requires transfusions of platelets and red cells, which are given until the donor stem cells start making blood cells in the recipient. The preparative regimen varies in intensity, going from very intense, strong chemo/radiation (called myeloablative conditioning) to regimens of lower intensity that use less chemo and/or radiation (reduced intensity conditioning or mini transplants).
The speed of blood recovery depends also on the source of stem cells. Umbilical cord blood is generally the slowest, while white stem cells from the blood are the fastest.
Factors That Help Determine Transplant Success
The likelihood of a successful transplant depends on a variety of factors, including:
- The disease and the stage of the disease
- Genetic makeup
- The amount and strength of prior treatments the patient received
- The patient’s overall health, presence or absence of other health problems (such as heart problems and others), and the patient’s age
- In donor transplants, recipient-donor matching degree; the better the match, the better the outcomes