Radiotherapy to the whole body is called total body irradiation or TBI.
Why you might have TBI
Radiotherapy is a treatment that uses high energy rays, similar to x-rays. You might have TBI alongside high dose chemotherapy drugs as part of your preparation for a stem cell or bone marrow transplant.
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)
TBI alongside chemotherapy helps to kill off leukaemia, lymphoma or myeloma 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.
Having total body irradiation
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. They rotate around you to give you your treatment. The machine doesn't touch you at any point.
Before you start your course of treatment your radiographers explain what you will see and hear. In some departments the treatment rooms have docks for you to plug in your music player. So you can listen to your own music.
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 various parts of your body and 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 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.
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.
Research continue to look at the role of TBI in stem cell or bone marrow transplants. Some researchers are trying to find out if a reduced dose of TBI is useful. It might be an option for those people who are unable to have high dose chemotherapy and standard doses of TBI. It could causes fewer side effects, but there may be an increased risk of the cancer coming back (relapse).
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)