Stem cell transplant for non-Hodgkin lymphoma

A stem cell transplant replaces stem cells. It uses chemotherapy at very high doses to kill all of the cells in the bone marrow. This includes both healthy cells and cancer cells. Sometimes whole body radiation therapy is also used. After high-dose chemotherapy, healthy stem cells are given to replace the ones in the bone marrow that were killed.

Stem cells are found in bone marrow, blood and umbilical cords. They are basic cells that develop into different types of cells that have different jobs. For example, all our blood cells develop from blood stem cells.

This treatment is used to replace stem cells when stem cells, the bone marrow or both are damaged. A stem cell transplant is very risky and complex, and it must be done in a special transplant centre or hospital.

A stem cell transplant is sometimes used to treat non-Hodgkin lymphoma (NHL). You may be offered a stem cell transplant to treat NHL if:

• it comes back after treatment (called relapsed NHL)
• you have an aggressive (fast-growing) type of NHL that is likely to come back after treatment
• it is in many lymph nodes, the bone marrow or other organs
• it doesn't respond or stops responding to other treatments (called refractory NHL)

The following types of stem cell transplants may be used with NHL.

The stem cells are taken from your own bone marrow or blood. An autologous stem cell transplant is done most often for NHL. But it may not be possible to do this type of transplant for some types of NHL if they have spread to the bone marrow or blood. This is because it can be difficult to get enough normal stem cells.

The stem cells are taken from one person (the donor) and given to another person (the recipient). The donor and recipient may or may not be related. The donor and recipient are matched through a process called human leukocyte antigen (HLA) typing.

An allogeneic transplant may be done if the NHL has spread to the bone marrow or blood. But not everyone can have an allogeneic transplant because they need to match with a donor.

A mini-transplant may also be called a reduced-intensity allogeneic transplant or non-myeloablative transplant. It uses lower doses of chemotherapy or radiation therapy before the transplant. The lower doses don't completely destroy the recipient's bone marrow, so blood cell counts don't drop as low as they do with standard stem cell transplants. Healthy stem cells are then given. Over time, the donor cells take over the bone marrow and replace the recipient's own bone marrow cells.

A mini-transplant has a lower risk for complications than autologous or standard allogeneic transplants. It can be used for older adults who can't tolerate the higher doses of chemotherapy and radiation normally used with stem cell transplants. People in this age group may also have other health conditions that won't allow them to have an allogeneic transplant.

Side effects of stem cell transplant will depend mainly on the type of chemotherapy or drug combination given, if radiation therapy was given, the type of transplant and your overall health. Tell your healthcare team if you have side effects that you think are from a stem cell transplant. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Side effects of a stem cell transplant include:

• low blood cell counts, which can cause infection, bleeding and anemia
• graft-versus-host disease (GVHD)
• veno-occlusive disease (VOD)
• digestive system problems, including sore mouth and throat, loss of appetite and diarrhea
• skin problems
• pain
• organ problems, such as kidney, lung or heart problems
• fertility problems
• graft failure or graft rejection
• osteoporosis
• a second cancer

Find out more about a stem cell transplant and side effects of a stem cell transplant. To make the decisions that are right for you, ask your healthcare team questions about a stem cell transplant.