What is involved in a donor stem cell (allogeneic) transplant?

Before a donor stem cell transplant, you will be given treatment to get you ready for your donor’s cells. This is called conditioning treatment. You will go into hospital about a week before your transplant date. You will be given advice about what to bring to make your stay more comfortable. They will also tell you any rules about visitors.

There are different ways of giving conditioning treatment and different levels of intensity (strength) of treatment. The conditioning treatment you have will depend on the type of cancer or leukaemia you have, your general health, and any chemotherapy or radiotherapy treatment you have had in the past.

You will have a combination of chemotherapy drugs through your PICC or central line. Some people also receive radiotherapy to the whole body (total body irradiation).

One or two days after you finish your conditioning treatment a nurse will give you the donated stem cells through your central or PICC line. The stem cells travel through your blood to your bone marrow, where they’ll engraft and start to make blood cells.

Going into hospital

About a week before the transplant, you will go into hospital to start conditioning treatment. You will usually be looked after in a room of your own but this can depend on the unit you are in. You will be staying in your room for at least a few weeks, so you might want to take some things from home.

What to take

The nurses will suggest what to take to keep you busy and make you more comfortable. You could take a laptop, radio, MP3 player, audiobooks or relaxation CDs, books and magazines.

You may also be able to take films, computer games, games or a hobby, such as knitting. Many hospitals have TVs and DVD players, and some have internet access.

You can take personal things, such as photos, pictures and maybe a clean blanket or pillow.

Take some comfortable, loose-fitting clothes. Soft, cotton materials are best, and tops with buttons will make it easier when you are being examined. An eye mask and ear plugs to help you to sleep can also be useful.

Ask the nurses for advice about the toiletries you should bring with you.


Visitors, especially close family and friends, are important.

They give you support and help you keep in touch with life outside hospital. Some units have rooms where family members can stay overnight. This is useful if your relatives have to travel to hospital.

Most hospitals are flexible about visiting, but different hospitals have different rules. You may be restricted to a certain number of visitors each day to help protect you from infection. The nurses will explain more about this to you.

Questions you might want to ask

  • How many visitors can I have and how long can they stay?
  • Is there anyone who shouldn’t visit, such as children?
  • What precautions will visitors have to take when they come to see me?
  • Can I bring my mobile phone? Is there a phone I can use, and will I need coins or a phone card?
  • Can I bring a laptop or tablet, and will I have access to the internet?
  • Do I need to follow a special diet? Are there any foods that I should avoid?

Having conditioning treatment

Before the transplant, you have conditioning treatment to get you ready for your donor’s cells. It usually involves having several different chemotherapy drugs. Some people also have radiotherapy to the whole body, called total body irradiation (TBI). You may also be given antibody therapy.

Your conditioning treatment can take up to two weeks. Your doctor will talk to you about the type of conditioning treatment that is best for you.

Conditioning treatment is given to:

  • get your body ready to accept the donor stem cells
  • weaken your immune system to reduce the risk of it attacking the donor stem cells
  • remove any remaining cancer or leukaemia cells from your body.

During conditioning treatment, your doctors may talk about days as numbers. The day of your transplant (stem cell infusion) is Day 0. The days before transplant are counted as Day –8, Day –7, and so on. The days after transplant are counted as Day +1, Day +2, and so on.

You usually finish conditioning treatment 24 to 48 hours before the transplant (Day –2 or Day –1).

If your donor is a relative, their stem cells are collected the day before the transplant. If your donor is not related, their stem cells are collected two days before the transplant. This is to make sure you are ready for the transplant soon after the stem cells are available.

There are different types of conditioning treatment and different levels of intensity (strength) of treatment. Your conditioning treatment depends on the type of cancer or leukaemia you have and your general health. Doctors will also consider any chemotherapy or radiotherapy that you have had in the past.

Full-intensity conditioning

You have very high-doses of chemotherapy, sometimes with total body irradiation (TBI) to destroy your bone marrow and immune system. This is to prepare you for having the donor stem cells.

Reduced-intensity conditioning

This uses fewer or lower doses of chemotherapy or radiotherapy, which should reduce the risk of transplant complications. But it weakens your immune system enough to allow the donor stem cells to grow in your bone marrow.

When both your donor’s cells and your own cells are in your system, this is called mixed chimerism. The donor stem cells will gradually replace your immune system and attack any remaining cancer cells in your body.

Having chemotherapy

The chemotherapy drugs are given through your central line or PICC line with plenty of fluids. The treatment is usually given over several days. You may get different side effects as a result of having low numbers of blood cells. Your doctor and nurse will explain how these can be managed. You will be given drugs to help control certain side effects.

We have information on chemotherapy that explains the treatment and how to cope with side effects. We also have information on individual drugs and drug combinations.

Total body irradiation (TBI)

Radiotherapy uses high-energy rays to destroy cancer cells. TBI treats your whole body with radiotherapy and some people have it as part of their conditioning treatment. You usually have it a few days after you start chemotherapy.

You may have TBI twice a day for 6 to 8 sessions over 3 to 4 days. If you are having reduced-intensity conditioning, you may only need one or two low doses of TBI or none at all.

You will have a planning session in the radiotherapy department a few days before you have TBI. The doctor will explain more about the treatment and its side effects.

Before each session, the radiographer (person who gives the treatment) positions you carefully and makes sure you are comfortable. Radiotherapy is not painful, but you need to keep still during the treatment. You have radiotherapy to both sides of your body so you need to change position a few times during the session. The radiographer will explain this to you.

During treatment, you are alone in the room but you can talk to the radiographer through an intercom. Each session lasts about 40 minutes, but the radiotherapy itself only takes about 10 to 20 minutes. You can bring some CDs to listen to during your treatment.

Side effects

Possible side effects of TBI include skin changes, tiredness, feeling sick, diarrhoea and a sore mouth. These can happen a few days later. The radiographers will explain how to manage the side effects and how to care for your skin.

Our booklet Understanding radiotherapy has more general information about radiotherapy.

Antibody therapy

You may be given a type of targeted therapy antibody drug to help damage your immune system. This is to allow the donor cells to grow and make new blood cells. The drug may also reduce the risk of graft-versus-host disease (GVHD).

You have the antibody drug given as a drip. Some people may have a reaction to it, which can sometimes be severe. You may have a fever and sometimes shivering (rigors). You will be given drugs to try to prevent or reduce a reaction before you have the antibody therapy. The nurses will monitor you closely.

You may also get an itchy rash that is sometimes raised on the skin. We have more information about targeted therapy drugs.

Late effects

Conditioning drugs and total body irradiation may cause side effects that can happen months or years after treatment is over. These are called late effects.

Having the stem cells

You have your transplant of donor stem cells a day or two after finishing conditioning treatment. The transplant day is known as Day 0.

Your nurse gives you the stem cells as a drip (infusion) through your central or PICC line. It is like having a blood transfusion.

Some people have mild side effects while the stem cells are being given, such as feeling sick or breathless. Your nurse will give you drugs through your central line before the stem cell infusion to reduce the risk of an allergic reaction. They monitor you carefully during and after the stem cell infusion.

For some people, having the stem cells may be an emotional experience. But it may also seem like any other day in hospital. There is no right or wrong way or to feel about it.

Waiting for the stem cells to grow

The stem cells travel through your blood to your bone marrow, where they start growing and making new blood cells. Doctors call this engraftment.

Until your donated cells start making new blood cells, you will have low numbers of all types of blood cells. This causes some of the main transplant side effects. You will have a high risk of getting an infection, of bleeding and of being anaemic (low red cells). While you are waiting for the donor cells to make new blood cells, your transplant team will care for you and monitor you very closely for complications.

It can be from 10 days to three weeks before some of the new blood cells are released into the blood. If you had a cord blood transplant or a haploidentical transplant it can take longer than this.

You may be given a drug called a growth factor as an injection. It stimulates your bone marrow to make new blood cells and reduces the length of time you are at risk of side effects.

PICC lines and central lines playlist

Watch our short animated videos about having PICC lines and central lines put in.

PICC lines and central lines playlist

Watch our short animated videos about having PICC lines and central lines put in.

Your daily routine

Although you may expect to have a lot of time on your hands, your days may be quite busy. A lot of your time will be taken up with daily routines and checks by the doctors and nurses looking after you. This will include:

  • taking blood samples from your line
  • giving medicines into your line
  • changing your drip (infusion) of fluids when needed
  • taking your temperature, pulse and blood pressure
  • examining your tummy and mouth
  • measuring the fluid you take in and the fluid you pass out (fluid balance)
  • checking your weight.

You will also be seen regularly by the dietitian, physiotherapist and other members of the team looking after you.

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