Allogeneic stem cell transplant (donor stem cells)

About an allogeneic transplant

This page is about an allogeneic transplant. This is also called an allograft.

This is different to an autologous transplant, which uses your own stem cells, instead of stem cells from a donor.

Read about a transplant using your own stem cells

Doctors usually collect stem cells from the donor's bloodstream, but sometimes they take them from the donor's bone marrow. Some people might have stem cells from donated umbilical cord blood. Cord blood is used less often than other types of transplant.

Why you might have a donor transplant

Your medical team look at a number of factors to decide whether you have a donor transplant. These include: 

• your type of cancer

• what other treatments you have had

• your general health

• whether your medical team can find a suitable donor or match

Read more about stem cells and how a transplant works

Stages of a donor transplant

There are different steps or stages of an allogeneic transplant.

Preparation 

Your healthcare team may work with you to prepare you physically and mentally for your stem cell transplant. This is called prehabilitation or prehab. It focuses on diet, exercise, mental health and lifestyle.

Find out more about preparing for treatment

Before your transplant, you have:

• tests to check your general health

• a central line put in

• a fertility appointment if this is relevant

• a dental check up

As part of your preparation, you might have chemotherapy to get rid of as many cancer cells as possible. This chemotherapy can also help the bone marrow make more stem cells.

Tests

Before you have a stem cell transplant, you have various tests to make sure you are well enough.

Tests you may have include:

• blood tests to check your levels of blood cells and how well your liver and kidneys are working

• blood tests to check for viruses such as hepatitis B, hepatitis C and human immunodeficiency virus (HIV)

• a chest x-ray

• lung function tests

• tests to look at how your heart is working, such as an ECG, or an echocardiogram (ECHO)

• a bone marrow test

• scans, such as a PET scan, CT scan or MRI scan

Central line

A central line is a long plastic tube that goes into your bloodstream. A doctor usually puts this line into a vein in your chest. This line stays in place for many months and means you don't need to have needles in your hands or arms each time you have treatment.

Your healthcare team use it to:

• give chemotherapy and other treatments

• give anti sickness medicines and antibiotics

• take blood samples

Find out more about central lines

Fertility

Your treatment could mean it is difficult to become pregnant or get someone pregnant. Talk to your healthcare team if this is a concern for you. You might be able to store sperm or eggs before starting treatment.

For women, treatment can sometimes cause an early menopause. Sometimes it is possible for women to freeze their eggs, embryos or ovarian tissue before starting cancer treatment. But these procedures take time. If you need to start treatment straight away, there may not be time for you to have a fertility treatment.

Men may be able to bank sperm before starting any treatment.

Ask your doctor and nurse if you're not sure about anything. They can explain what your options are.

Find out more about fertility when you have cancer

Dental check up

It's important to have a dental check up before starting your stem cell transplant. You should also have any dental treatment beforehand, such as fillings, tooth removal, or treatment for gum disease. This is because your immune system will be weaker during treatment, making it harder for your body to fight infections. Even minor tooth problems that seem fine now could become serious during treatment.

Finding a donor

Ideally, your donated stem cells need to match your own. Your body is more likely to accept the donor stem cells if they do. A brother or sister is most likely to be a close match. Having cells from a matched sibling is the first choice for a transplant.

Sometimes, if you don't have a brother or sister who is a match, you can have stem cells from another person. This could be a donor who is not related to you but whose stem cells are similar to yours. This is called a matched unrelated donor (MUD) transplant.  

Some people might have stem cells that are not a perfect match (but partly match). This is called a mismatched transplant.

Conditioning

Once a donor is found, you have conditioning treatment. You will need to stay in hospital for a few weeks during your conditioning and after you have your donor's stem cells.

There are different drugs and regimes. What you have depends on your individual circumstances. There are also different strengths of conditioning treatment. The 2 main types are:

• full intensity (myeloablative) conditioning

• reduced intensity conditioning (RIC)

Full intensity conditioning (MAC)

Your doctor might also call this myeloablative conditioning or MAC. You have very high doses of chemotherapy. When stem cell transplants were first developed, this was the type of conditioning that everyone had. With MAC, all of the cancer cells and healthy cells are destroyed. Your doctor might recommend you have MAC if you are young and you have certain types of cancer. For example, if you have acute leukaemia.

As well as chemotherapy, you might also have:

• targeted drugs

• radiotherapy to the whole body (total body irradiation or TBI)

You usually have TBI at the beginning or at the end of your chemotherapy.

Reduced intensity conditioning (RIC)

This reduced intensity treatment is also called nonmyeloablative conditioning. With RIC you have lower doses of chemotherapy. Some healthy cells and cancer cells are left behind after treatment has finished. You might have RIC if you are not fit or well enough for full intensity conditioning. This is now the standard conditioning treatment for most types of cancer. You might also have targeted drugs with your chemotherapy.

RIC can have fewer side effects. But there is a greater risk of the cancer coming back, compared to MAC. Even though the doses of chemotherapy are lower, this can still be a difficult treatment to cope with. Your healthcare team monitor you closely throughout your treatment and when you go home. 

Conditioning treatment can take about 7 days. But it could be shorter or longer depending on the drugs you have.

Look for more information about your drug treatment

Find out more about total body irradiation

You have your donor's stem cells

After you have your chemotherapy and other treatments you have your donor's stem cells. This is your transplant. Your healthcare team give you the stem cells as an infusion through your central line and into your bloodstream.

Before this, your nurse will give you medication to help prevent allergic reactions and reduce any side effects. You may also have fluids through a drip.

The process is similar to having a blood transfusion and is not painful. You are awake throughout and the nurse regularly checks your blood pressure and temperature.

Blood count recovery

After your transplant, the donor stem cells find their way into your bone marrow where they begin making new blood cells. This is called engraftment.

You have regular blood tests to check when your bone marrow starts to make new blood cells.

During this time, you continue to have treatment for any side effects and symptoms. This might include:

• antibiotics and antiviral medicines to treat and prevent infection

• platelet transfusions if the number of platelets in your blood is low

• blood transfusions if your red blood cells are low

• medicines to relieve a sore mouth, diarrhoea and sickness

• medicine to prevent or treat graft versus host disease (GvHD)

Preventing and treating GvHD

To lower your risk of developing GvHD, you will have medication before or after your transplant. Or both.

Drug treatments to prevent GvHD include:

• immunosuppressants such as ciclosporin, anti thymocytic globulin (ATG) and mycophenolate mofetil (MMF)

• chemotherapy drugs such as cyclophosphamide and methotrexate

• a monoclonal antibody called alemtuzumab

If you do develop GvHD, you may need to stay in hospital for longer. Treatment depends on what type of GvHD you have, where you have it and how severe it is.

Read more about GvHD

Hospital stay

After conditioning treatment, you have low numbers of blood cells for some time. This means you are at risk of getting infections. You usually stay in hospital until:

• your blood cells have recovered enough for you to go home

• you no longer have any severe side effects 

This might take 4 or 5 weeks following a donor transplant, although this time can vary from one person to another. 

Isolation

You might have a single room in the hospital ward to help protect you from infection. Your medical team might call this being in isolation. 

While you are in isolation you can have visitors, but you might only be allowed one or two each day. In some hospitals you need to have the same two visitors whilst you are in isolation. Your friends and relatives should not visit if they are unwell. Or if they have been in contact with anyone with an infectious disease.

You might need to follow a special diet including foods that are unlikely to give you an infection. 

Coping with isolation

Staying in a single room in hospital can feel lonely. Some people find it frightening. It can help to talk to your nurses and healthcare team about your worries. They can reassure and support you. 

Taking in some of your personal things can make the room feel more homely. Books and photos can brighten it up. You can also take in a laptop, tablet, mobile phone and music. This can help pass the time and you can keep in touch with friends and family.

Recovery and follow up after a transplant

Recovery after a transplant can take a while. You will have regular follow up appointments, which will become less frequent over time.

Find out more about recovery after a transplant

Things that happen in follow up include:

• checking your blood cell levels and general recovery

• chimerism testing

• find out how well the treatment has worked

• managing any side effects or problems

• having donor lymphocyte infusions (DLI)

Chimerism testing

Your doctor measures the proportion of cells that are from your donor. After RIC, it is normal at first to have some of your donor stem cells and some of your own cells. This is called mixed chimerism. Eventually, all your blood and bone marrow should ideally be from your donor. This is called full chimerism. 

You have tests to check for chimerism every few months for about a year after your transplant.  

Donor lymphocyte infusion (DLI)

Lymphocytes are a type of white blood cell. They are part of the immune system.

You might have some of your donor's lymphocytes as a drip into your bloodstream. Increasing the number of donor cells helps the immune system get rid of any remaining cells. So eventually you have full donor chimerism. You are more likely to need donor lymphocyte infusions if you have a transplant following RIC. Some people might need quite a few of these infusions. Other people may not need any. 

You usually have donor lymphocyte infusions after you go home and as an outpatient.

Side effects of transplants

Side effects of a donor transplant include:

• an immune reaction which can cause a rash, diarrhoea and liver problems

• increased risk of getting an infection 

• tiredness and lack of energy

• increased risk of bleeding

• sickness and diarrhoea

Read about the side effects of a stem cell or bone marrow transplant