Bone marrow (stem cell) transplant and donation
A transplant of the stem cells that form in bone marrow can help people recover from certain types of cancers and blood and bone marrow disorders, but having a bone marrow or stem cell transplant can require a donation from someone.
What is bone marrow and why do we need it?
The bones of the body are hollow and in the centre – especially in the flat bones such as the breastbone and pelvis – can be found a soft tissue known as bone marrow. This sponge-like substance produces stem cells. These are immature cells that constantly divide to produce new cells, some of which grow into mature blood cells used by the body. These include:
- Red blood cells for carrying oxygen around the body
- White cells for fighting infections
- Platelets that help stop bleeding
Stem cells need to divide rapidly to make millions of blood cells every day. Without these stem cells it would be impossible to survive.
Why would someone need a bone marrow transplant?
People who have a condition that damages bone marrow may not have enough stem cells to produce normal blood cells. This can occur if there is a type of bone marrow failure or a genetic blood or immune system disorder.
In other cases, treating people with certain types of cancer sometimes requires giving very high doses of chemotherapy to kill the cancer cells in the body. Whole body radiotherapy may also be used to kill off the cancer cells. However, these treatments can also kill healthy cells in the body, including the stem cells in bone marrow.
People who may need a bone marrow transplant include those with:
- Aplastic anaemia (bone marrow failure)
- Leukaemia (cancer of the white blood cells)
- Non-Hodgkin lymphoma (cancer of the lymphatic system)
- Myeloma (a cancer of the bone marrow)
- Sickle cell anaemia (a genetic blood disorder)
- Thalassaemia (a genetic blood disorder)
How is a bone marrow or stem cell transplant performed?
The collected stem cells are added to a solution that is put into the body by using a drip, similar to receiving a blood transfusion. These cells enter the bloodstream and then travel to the bones, where they can start producing blood cells again. In people who have cancer, this is performed the day after treatment with chemotherapy or radiotherapy ends.
Because having a transplant involves being given different drugs and blood transfusions as well as the transplant itself, the patient may be given a central line, or central venous catheter. An operation will be performed to insert a thin tube through the skin near the collarbone and into a large vein near the heart.
The transplant itself isn't painful, but the person will need to remain in hospital for between 5 to 6 weeks while their bone marrow recovers, allowing time for the donated stem cells to settle in and start producing new cells. Antibiotics are often given to limit the risk of infection, which is particularly high during this period and the reason why the person may be placed in isolation. Blood transfusions may also be necessary until the bone marrow is making enough new blood cells. The person will also be monitored to ensure the stem cells have been accepted.