Bone Marrow Transplants and Stem Cell Transplants for Cancer Treatment
Chemotherapy and Radiation Therapy
Before you get the stem cell transplant, you’ll get the actual cancer treatment. To destroy the abnormal stem cells, blood cells, and cancer cells your doctor will give you high doses of chemotherapy, radiation therapy, or both. In the process, the treatment will kill healthy cells in your bone marrow, essentially making it empty. Your blood counts (number of red blood cells, white blood cells, and platelets) will drop quickly. Since chemotherapy and radiation can cause nausea and vomiting, you might need anti-nausea drugs.
Without bone marrow, your body is vulnerable. You won't have enough white blood cells to protect you from infection. So during this time, you might be isolated in a hospital room or required to stay at home until the new bone marrow starts growing. You might also need transfusions and medication to keep you healthy.
What Happens During the Stem Cell Transplant?
A few days after you’ve finished with your chemotherapy or radiation treatment, your doctor will order the actual stem cell transplant. The harvested stem cells -- either from a donor or from your own body -- are thawed and infused into a vein through an IV tube. The process is essentially painless. The actual stem cell transplant is similar to a blood transfusion. It takes one to five hours.
The stem cells then naturally move into the bone marrow. The restored bone marrow should begin producing normal blood cells after several days, or up to several weeks later.
The amount of time you’ll need to be isolated will depend on your blood counts and general health. When you are released from the hospital or from isolation at home, your transplant team will provide you with specific instructions on how to care for yourself and prevent infections. You’ll also learn what symptoms need to be checked out immediately. Full recovery of the immune system might take months or even years. Your doctor will need to do tests to check on how well your new bone marrow is doing.
There are also variations in the stem cell transplant process being studied in clinical trials. One approach is called a tandem transplant, in which a person would get two rounds of chemotherapy and two separate stem cell transplants. The two transplants are usually done within six months of one another.
Another is called a “mini-transplant,” in which doctors use lower doses of chemotherapy and radiation. The treatment is not strong enough to kill all of the bone marrow -- and it won’t kill all of the cancer cells either. However, once the donated stem cells take hold in the bone marrow, they produce immune cells that might attack and kill the remaining cancer cells. This is also called a non-myeloablative transplant.