What is a matched unrelated donor stem cell transplant?

Being diagnosed with blood cancer or a blood disorder can be a stressful and worrying time for both you and your loved ones. You need healthy bone marrow and blood cells to stay fit and well.

If you have a condition that affects your bone marrow or blood, then a stem cell transplant could be your best treatment option. For some people, it offers hope of a potential cure.

During your transplant your medical team will put new, healthy stem cells into your bloodstream. After a period of time they will attach to your bone marrow (called engraftment) and start to make new blood cells. Your new stem cells will be selected from a volunteer donor who is closely matched to you genetically – giving you the best possible chance of overcoming your condition.

Who might need a matched unrelated donor transplant?

A matched unrelated donor (MUD) transplant could be a treatment option for you if you have:

If you do not have the option of a sibling match, your transplant centre will get in touch with Anthony Nolan to find you a suitable donor. We’ll search all donors on the registry as well as every potential donor available internationally. For more information about this process see Finding a donor for your stem cell transplant.

Anthony Nolan found the perfect match for me, and that is probably why I am doing so well now. People who look at me now don't even realise that I was ever sick, which is a great feeling.

Amanda received stem cells from an unrelated donor to treat her AML. You can read her story here.

What will happen before the transplant?

You will have conditioning therapy to prepare your bone marrow and immune system for the new stem cells. This is done with chemotherapy, sometimes in combination with a type of radiotherapy called total body irradiation (TBI). This also removes remaining abnormal cells causing your condition.

What will happen during the transplant?

Your transplant normally takes place the day after conditioning therapy finishes. The transplant itself involves the donor stem cells (a small bag of pale red liquid) being passed through a thin tube into your bloodstream, just like having a blood transfusion. The transplant isn’t painful and you’ll be awake the whole time.

Recovering from a matched unrelated donor transplant

You’ll probably be in hospital for about 3-4 weeks after your transplant. You’ll need to spend some time in protective isolation while your immune system starts to recover. This usually means that you’ll be in your own single room with precautions put in place to reduce the risk of you picking up an infection. For more information about how to cope during this time, see Your stay in protective isolation.

Your recovery is likely to affect many aspects of your life and it could take six months to a year before your activity levels start to get back to normal. More information and advice can be found in our website’s Recovery page.

What side effects can I expect?

Having a transplant is a very intensive treatment that will impact you both physically and emotionally. Your transplant team will talk to you about the risk of complications and side effects so you can make the best decisions for your care.

Side effects of an MUD transplant vary from person to person and can be short-term or long-term. They are often caused by the conditioning therapy you have before the transplant, as well as the transplant itself.

Short-term side effects include:

  • increased risk of infections
  • sore mouth (mucositis)
  • liver and kidney problems
  • tiredness
  • diarrhoea and feeling or being sick
  • loss of appetite.

You might also feel down at times and find it difficult to cope with your situation. This is perfectly normal and understandable. Your transplant team will be on hand to listen to your concerns and may be able to refer you to a therapist for further support. We have further information on this in our Recovery section.

Long-term side effects include:

When you’ve had a stem cell transplant, there are still small differences between your new developing immune system and other cells in your body. As a result, your growing immune system may harm some of the cells in your own body because it sees them as ‘different’. This is called graft versus host disease (GvHD).

It can affect different parts of your body, but commonly affects your skin, gut and liver. It can be short or long-term, and mild or severe. Your transplant team will be monitoring you closely for signs of GvHD and will offer you treatment that can help. We have further information on our GvHD webpage.

For more information on the long-term effects of a transplant, read our booklet The Seven Steps: The Next Steps.

Information published: 05/08/21
Next review due: 05/08/24  

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