What You Should Know about Stem Cell Transplants
Listen to the podcast
A stem cell transplant is a procedure that replaces defective or damaged cells in patients whose normal blood cells have been affected by cancer. Transplants also are used to help patients recover from aggressive radiation and chemotherapy treatments.
Stem cells are immature cells that begin life in the bone marrow and eventually develop into the various types of mature blood cells:
There are three types of stem cell transplantation:
Autologous transplant: cells are harvested from the patient's own bone marrow before chemotherapy and are replaced after cancer treatment.
Allogeneic transplant: stem cells come from a donor whose tissue most closely matches the patient.
Umbilical cord blood from newborn infants is extracted from the placenta after birth and saved in special cord blood banks for future use. MD Anderson's Cord Blood Bank actively seeks donations of umbilical cords.
Stem cell transplants commonly are used to treat leukemia and lymphoma, cancers which affect the blood and lymphatic system. Transplants also can be used to help patients recover from or better tolerate cancer treatment, and to treat hereditary blood disorders such as sickle cell anemia.
Stem cell transplant patients are matched with eligible donors by human leukocyte antigen (HLA) typing. HLA are proteins that exist on the surface of most cells in the body. HLA markers help the body distinguish normal cells from foreign cells, such as cancer cells.
HLA typing is done with a patient blood sample, which is then compared with samples from a family member or a donor registry. It can sometimes take several weeks or longer to find a suitable donor.
The closest possible match between the HLA markers of the donor and the patient reduces the risk of the body rejecting the new stem cells (graft versus host disease).
The best match is usually a first degree relative (children, siblings or parents). However, about 75% of patients do not have a suitable donor in their family and require cells from matched unrelated donors (MUD), who are located through registries such as the National Marrow Donor Program.
Because the patient’s immune system is wiped out before a stem cell transplant, it takes about six months to a year for the immune system to recover and start producing healthy new blood cells. Transplant patients are at increased risk for infections during this time, and must take precautions. Other side effects include:
As a volunteer with CanCare and myCancerConnection, MD Anderson's
one-on-one program that connects cancer patients and caregivers with
others who have been there, I talk to a lot of other multiple myeloma
patients. Most ask about the stem cell transplant process and my
Here's what I tell them.
What to know about autologous stem cell transplants
A transplant infuses health cells -- also known as stem cells...