What is an autologous stem cell transplant?

In autologous stem cell transplants, the patient is their own stem cell donor. These cells are collected in advance (while they are in remission) and returned to the patient at a later stage. They are used to replace stem cells that have been damaged by high doses of chemotherapy, used to treat the patient’s underlying disease.

Autologous transplants are used to treat a number of different blood cancers. Autologous transplants allow the use of high-dose chemotherapy, which provides some patients with a better chance of cure or long-term control of their disease. Most people have a single autologous transplant. Others, particularly those with myeloma or some solid tumours, may have two or more sequential (one after the other) transplants, over a period of a few months.

It’s important to realise that the processes involved in a stem cell transplant are often long and complex. A transplant involves a lot of preparation and a lot of aftercare. The process of a stem cell transplant can be divided into these nine different stages:

1. planning for your transplant
2. pre-transplant “work-up”
3. conditioning therapy
4. the transplant
5. pre-engraftment
6. potential post-transplant complications
7. leaving hospital
8. potential late side effects
9. recovery.

How does the transplant work?

Stem cells are usually collected when the patient’s disease is in remission or their disease is in a more stable state. In autologous stem cell transplantation, stem cells are collected (or “harvested”) from either the bone marrow, bloodstream (called a peripheral blood stem cell harvest), or sometimes a combination of both. It is more common these days to collect bone marrow stem cells from the bloodstream. Stem cells normally live in the bone marrow, but they can be encouraged to move out of the bone marrow and into the bloodstream. This process is called stem cell mobilisation and usually involves the use of chemotherapy in combination with colony stimulating growth factor injections – usually G-CSF. G-CSF promotes the production of stem cells in the bone marrow which then leak out into your normal blood circulation in your veins. Growth factor injections are usually given for several days, usually starting 24 hours after the completion of your chemotherapy.

Regular blood tests will be taken over the following week to identify the best day to start collecting your stem cells. It is important to keep taking your injections of growth factors at the same time every day until you are told to stop. Stem cells are collected from your bloodstream by passing all your blood through a special machine called a cell separator (or apheresis machine). The apheresis machine draws blood from the body, spins the blood very quickly, collects the part that contains the blood stem cells, and returns the rest of the blood back to the body. This is a continuous process.

Conditioning therapy

In the week leading up to your transplant you will be given a few days of very high-dose chemotherapy, and sometimes radiotherapy, to destroy your underlying disease. This is called conditioning therapy. Conditioning therapy is used to help destroy any leftover cancer cells in your body and to make or create a space in your bone marrow for the new stem cells to grow.   After you have finished this treatment, your stem cells are thawed and reinfused through a vein into your bloodstream. This is similar to a blood transfusion. From here the stem cells make their way to your bone marrow where they become re-established and start making new blood cells.

In the week following the transplant, your blood counts drop dramatically. This is to be expected. During this time you will be more at risk of infections (due to the lack of infection-fighting white blood cells) and bleeding (due to a lack of platelets). Antibiotics and other drugs are commonly prescribed to help prevent or treat infections during this time, and you are likely to need platelet transfusions to reduce your risk of bleeding.

Red blood cell transfusions are given when your haemoglobin levels are too low. During this time you are likely to be experiencing some of the common side effects of chemotherapy and radiotherapy which may include nausea, vomiting, mucositis (sore mouth) and bowel problems (diarrhoea). For more information on side effects of treatment please refer to our website’s section on your specific disease.

Leaving hospital after a transplant

Once your blood counts start to rise and you are otherwise well enough you are usually allowed to leave the hospital. In the early weeks after your transplant you will need to visit the hospital or clinic regularly so that the doctor can check your blood counts and see how you are progressing.

It can take a few months for your immune system to recover after an autologous transplant so it is important to take some sensible precautions to prevent infections during this time, such as avoiding contact with people with an illness like flu or chicken pox.

Recovery

It generally takes between three and six months to recover fully after an autologous transplant. During this time it is important to look after yourself and to try to focus on the things you can do to help yourself recover well both physically and emotionally.

The success of your transplant will depend on a number of factors including the type and stage of disease you have, your age and your general health. Important advances have been made in recent years, and continue to be made, improving the success of all types of transplants.

Despite this, many people experience a relapse of their original disease at some stage following an autologous transplant. If your disease relapses there are often ways of getting it back under control. These may include more chemotherapy and/or another transplant, or a drug to stimulate your immune system to fight the disease. Your doctor will advise you on your chances of relapse following an autologous transplant.