What Happens During Stem Cell Transplant for Non-Hodgkin Lymphoma
Stem cell transplants may be autologous, which means the stem cells come from your own body. Or they may be allogeneic, which means the stem cells come from a donor. Discuss the risks and benefits of each approach with your doctor beforehand. Here’s a general description of how a stem cell transplant is done.
Retrieving the needed stem cells
You or your donor may get an injection of a growth factor drug for several days. This drug helps stimulate stem-cell production. Then a small tube, called a catheter, is used to take blood from your vein or that of the donor. This is similar to donating blood, but it takes several hours. The blood goes to a cell separation device to remove the stem cells. Then the extra blood is returned to you or the donor. This process, called apheresis, may need to be repeated more than once.
Stem cells may also be collected from umbilical cord blood. After a baby is born, the blood from the placenta and umbilical cord is collected. This blood, which is rich in stem cells, is then frozen and stored until it is needed by someone with a matching tissue type.
Receiving the transplant
When a donor is used for the transplant, you eliminate the chance of lymphoma cells being returned to your body. But you may have more side effects, such as graft-versus-host disease, in which immune cells from the donor start attacking certain organs in your body.
You will then have to wait for your stem cells to start multiplying. This is referred to as engraftment. You may have to stay in isolation to help prevent getting an infection until that happens. Once the part of your white blood cell count called the ANC reaches a certain level (usually about 500), you can come out of isolation. Once it reaches 1,000, you can usually go home. This may take about 3 weeks.
If you get an allogeneic transplant, you may have a treatment called donor lymphocyte infusion (DLI) after the stem cell transplant. The goal is to help put your disease into remission or to keep it there. This treatment involves removing lymphocytes (a type of white blood cell) from the stem cell donor’s blood and freezing them. The lymphocytes are later thawed and given to you in 1 or more infusions. The donor’s lymphocytes will see any remaining lymphoma cells as not belonging to your body and will attack them.