Stem cell transplants

Bone marrow and blood stem cell transplantation (commonly referred to as simply stem cell transplantation) is used to treat a range of diseases. These include haematological (blood) disease such as leukaemia, as well as non-haematological diseases. The following list gives you some examples of conditions which can be treated with stem cell transplantation:

• leukaemia
• lymphoma
• myeloma
• amyloidosis
• aplastic anaemia
• some solid tumours (for example testicular cancer, breast cancer)
• some immune system disorders (for example scleroderma).

Stem cells are primitive blood-forming cells that normally live in the bone marrow. These stem cells can be likened to ‘baby’ cells that have not yet decided which type of blood cell they want to be when they grow up. They divide and mature into all the different types of blood cells (red cells, white cells and platelets), including the cells of our immune system and are therefore vital for our survival.

High-dose chemotherapy aims to destroy disease but, as an unwanted effect, it may also destroy the precious blood stem cells, which then need to be replaced. Sometimes stem cells also need to be replaced because they are diseased (for example in leukaemia) or defective (for example in aplastic anaemia).

In short, a stem cell transplant is necessary to ensure that the bone marrow is repopulated with healthy blood stem cells following high-dose treatment. The new blood stem cells will rebuild your body’s blood and immune systems.

Types of transplant

There are two main types of transplants: autologous transplants and allogeneic transplants.

The type of transplant you are given depends on a number of factors. These include the type of disease you have, your age, general health, the condition of your marrow and whether you would benefit by receiving donated stem cells, or whether your own stem cells can be used.

A stem cell transplant is not necessarily the best option for everyone. The transplant process is demanding both physically and emotionally, and some people may not be fit enough to tolerate it. In fact, many people don’t need a transplant and can be successfully treated using a less intensive approach. For others a transplant is the only option that offers a prospect of cure, or long-term survival.

Your doctor will spend time discussing with you and your family what he or she feels is the best option for you and your particular situation.

Autologous transplants

An autologous transplant uses the patient’s own stem cells, collected in advance and returned to them after they receive high doses of chemotherapy. Almost 2,000 stem cell transplants are carried out in Australia each year. The majority of these are autologous transplants.

Allogeneic transplants

In an allogeneic transplant the stem cells are donated from another person, who is a genetically-matched stem cell donor. While all transplants are serious procedures, allogeneic transplants are more complicated and therefore carry more short and long-term risks than autologous transplants.

Sources of stem cell transplants

In bone marrow and stem cell transplantation, stem cells can be harvested (or collected) from various sources.