A bone marrow transplant, more commonly known as a stem cell transplant, replaces damaged bone marrow with healthy bone marrow stem cells.
Bone marrow is a spongy tissue found in the hollow centres of some bones. It contains specialist stem cells which produce the body's blood cells.
Stem cells in bone marrow produce three important types of blood cells:
- red blood cells - which carry oxygen around the body
- white blood cells - which help fight infection
- platelets - which help stop bleeding
What is a bone marrow transplant?
A bone marrow transplant involves taking healthy stem cells from the bone marrow of one person and transferring them to the bone marrow of another person.
Bone marrow transplants are often needed to treat conditions that damage bone marrow meaning that it is no longer able to produce normal blood cells. The new stem cells take over blood cell production.
Bone marrow transplant is used to treat:
- severe aplastic anaemia (bone marrow failure)
- leukaemia - cancer of the white blood cells
- non-Hodgkin's lymphoma - cancer of the lymphatic system
- certain genetic blood and immune system disorders - such as sickle cell anaemia, thalassaemia and some severe immune system diseases
Read more about why a bone marrow transplant is needed.
In some cases, it may be possible to take your own bone marrow from another part of your body (autologous transplantation). The bone marrow is cleared of any damaged or diseased cells before it is returned.
The transplant procedure
A bone marrow transplant involves five stages. These are:
- a physical examination to assess your general level of health
- obtaining the stem cells to be used in the transplant (known as harvesting)
- preparing your body for the transplant (known as conditioning)
- transplanting the stem cells
- the recovery period during which you will be monitored for any complications or side effects
Having a bone marrow transplant can be an intensive and challenging experience. Many people take up to a year to fully recover from the procedure.
Read more about what happens during bone marrow transplant.
Who can have a bone marrow transplant?
Bone marrow transplants are usually only recommended if:
- the recipient is in relatively good health despite their associated condition (which is why they are often carried out when cancer is in remission)
- stem cells are available from a brother or sister or, less commonly, another family member, or an unrelated donor with the same or similar tissue type (this reduces the chances of the bone marrow being rejected)
- the associated condition is not responding to other forms of treatment and it is felt that the condition would respond to a transplant and could get worse without one
- it is felt that the benefits of a transplant outweigh the risks
Read more about who can have a bone marrow transplant.
Bone marrow transplants are complicated procedures with significant risks.
In some cases the transplanted cells (graft cells) recognise the recipient's cells as 'foreign' and try to attack them. This is known as graft versus host disease (GvHD).
The risk of infection is also increased because the immune system is weakened as you are conditioned (prepared) for the transplant.
Read more about the risks of having a bone marrow transplant.