Total body irradiation (TBI)

Radiotherapy to the whole body is called total body irradiation or TBI.

Why you have TBI

Radiotherapy is a treatment that uses high energy rays, similar to x-rays. As preparation for your stem cell or bone marrow transplant, you might have TBI at the same time as:

high dose chemotherapy drugs
targeted cancer drugs

It is a treatment for some people with:

lymphoma - cancer of the lymphatic system
leukaemia - cancer that develops in the white blood cells of the immune system
myeloma - cancer that develops in white blood cells called plasma cells
myelodysplastic syndromes (MDS) - a group of blood cancers where the bone marrow doesn’t work properly and makes abnormal blood cells

TBI alongside chemotherapy helps to kill cancer cells in the bone marrow. In a transplant using donor stem cells, TBI also suppresses the immune system. This helps to prevent a rejection of the donor stem cells.

How often do you have TBI?

You usually have TBI treatment twice a day for 3 or 4 days. Or it may be just 1 or 2 radiotherapy treatments. Radiographers give the treatment. They will explain to you how they plan the treatment and how you have radiotherapy.

The radiotherapy room

Radiotherapy machines are very big and could make you feel nervous when you see them for the first time. The machine might be fixed in one position. Or it might rotate around your body to give treatment from different directions. The machine doesn't touch you at any point.

Before your first treatment, your radiographers Open a glossary item will explain what you will see and hear. In some departments, the treatment rooms have docks for you to plug in music players. So you can listen to your own music while you have treatment.

Planning treatment

First you have a planning session of about 90 minutes to create the treatment plan. You take off any jewellery, your watch and your glasses. You will also need to take out false teeth containing metal. You lie down on a treatment couch or stand up in a specially designed frame.

Treatment lying down

Your radiographers measure the thickness of different parts of your body. They put small radiation monitors called diodes on your body. They might use padding material or gel bags between your knees and over your chest and neck. This is to make sure you receive an even dose of radiation throughout your body.

During the planning session, you lie on a couch. You have a very small dose of radiotherapy from a radiotherapy machine next to the treatment couch. The couch moves so you can have treatment to one half of your body. Then the couch turns so that the machine can give treatment to the other side.

Treatment standing up

You stand in a specially designed frame that supports you. First you stand facing the radiotherapy machine and then you turn so that your back is towards the machine.

Treatment sessions

Your radiographers help you get into exactly the same position as in your planning appointment. This can take up to half an hour. They tape small radiation monitors to some areas of your body to monitor the dose.

The lights in the room dim for a few minutes while the radiographers position you. They leave the room while the machine is on. But they can watch you closely on closed circuit TV during the treatment. It is important that you stay as still as you can but you can breathe normally. The treatment takes up to 15 minutes on each side of your body.

You have a buzzer that you can press at any time if you need the treatment to be stopped. You don't feel anything but when the machine is on you will hear a beeping noise.

Side effects

The possible side effects depend on a number of factors including:

your dose of TBI
the combination of cancer drugs you have (for example chemotherapy and targeted cancer drugs)

During the treatment and for some time afterwards you are likely to have:

sickness – you have anti sickness medicine to help prevent and treat this
tiredness – you might feel particularly tired about 6 to 12 weeks after your treatment and this could become severe for a couple of weeks
diarrhoea – tell your medical team if you have diarrhoea
a dry and sore mouth – your nurse will give you drinks, mouthwashes and painkillers to help
loss of taste and appetite
sensitive skin – your skin may go pink, darken and be itchy and more sensitive to the sun
complete head and body hair loss - this is usually temporary and will grow back gradually when treatment has finished

TBI and chemotherapy causes your blood levels to become low. So you are more at risk of infection, anaemia (low red blood levels) and bleeding. For example, bleeding gums and nosebleeds. You have treatment with antibiotics, blood transfusions and platelet transfusions if you need them.

Due to a high risk of infection, you may be looked after in a single room (isolation) in hospital.

Long term side effects

TBI can have long term effects. It can make your skin sensitive and you will need to be extra careful in the sun for several months after treatment. Talk to your specialist about the precautions you should take to protect your skin in the sun.

There are other long term effects that can be more permanent.

Lung changes

TBI can cause changes in the lung such as thickening or scarring of the tissue (fibrosis). This can cause breathlessness, coughing or wheezing. You will have regular tests to check how well your lungs are working. And you may need antibiotics to prevent infection. Breathing exercises can help.

Clouding of the lens of the eye (cataracts)

It is possible that you might develop cataracts several years after treatment. This means the lens inside your eye clouds over and it becomes increasingly difficult to see. This is less common now as you have radiotherapy over a few days.

Your doctor will refer you to an eye specialist (ophthalmologist) if you develop a cataract. Cataracts are fairly easy to treat with surgery. The eye specialist removes the clouded lens and puts a man made one in its place.

Fertility problems

Unfortunately, you are usually unable to become pregnant or father a child after TBI and high dose chemotherapy.

In women, the treatment is likely to cause an early menopause. Sometimes it is possible for women to freeze their eggs or embryos before cancer treatment. But it takes time to stimulate your ovaries to collect the eggs. Your doctor may not want you to delay starting cancer 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.

Underactive thyroid

A stem cell or bone marrow transplant can increase your risk of getting a second cancer. This is a worrying thought but it is important to remember that it is a very small risk. And it is less of a risk to your health than if your cancer was not treated.