Bone marrow transplantation and peripheral blood stem cell transplantation are procedures that restore stem cells that have been destroyed by high doses of chemotherapy and/or radiation therapy.
There are three types of transplants:
- In autologous transplants, patients receive their own stem cells.
- In syngeneic transplants, patients receive stem cells from their identical twin.
- In allogeneic transplants, patients receive stem cells from their brother, sister, or parent. A person who is not related to the patient (an unrelated donor) also may be used.
Bone marrow transplantation and peripheral blood stem cell transplantation are used in cancer treatment to make it possible for patients to receive very high doses of chemotherapy and/or radiation therapy — treatments that can severely damage or destroy the patient’s bone marrow.
The healthy, transplanted stem cells can restore the bone marrow’s ability to produce the blood cells the patient needs.
In some types of leukemia, the graft-versus-tumor effect (an immune response to a person's tumor cells by immune cells present in a donor's transplanted tissue) that occurs after allogeneic bone marrow transplantation and peripheral blood stem cell transplantation is crucial to the effectiveness of the treatment — when white blood cells from the donor (the graft) identify the cancer cells that remain in the patient’s body after the chemotherapy and/or radiation therapy (the tumor) as foreign and attack them.
See reference for details. National Cancer Institute. Blood-forming stem cell transplants. Internet. Accessed on May 16 2016.