External beam radiotherapy

Many types of external beam radiotherapy are conformal. This means the beams are specially shaped to fit the treatment area. Conformal radiotherapy can be used to treat many different types of cancer.

IMRT is often used to treat many types of cancer. IMRT shapes the radiotherapy beams and allows different parts of the treatment area to have different doses of radiotherapy. This means the healthy tissue surrounding the tumour has lower doses of radiotherapy. This can help reduce the risk of side effects and late effects. It may also allow the tumour to get higher doses of radiotherapy. 

For example, when used for pelvic tumours, IMRT can reduce the risk of long-term bowel problems. It may also reduce damage to the salivary glands and the risk of permanently having a dry mouth when used for head and neck tumours.

VMAT is a newer way of giving IMRT. It is sometimes called RapidArc^®. The radiotherapy machine moves around you and reshapes the beam during treatment. This makes it more accurate and shortens the treatment time.

IGRT uses the pictures from scans taken before, and sometimes during, each treatment. The pictures are compared to those taken during the planning scan to check your position and the treatment area. 

IGRT is helpful for treating tumours in areas of the body that change shape or position during or between treatment sessions. For example, it may be used to treat the prostate or cervix. These organs can change position if you have a full bladder or bowel on the day of your treatment. IGRT means the radiographers can adjust the treatment area before each treatment. This makes the radiotherapy very precise.

4D radiotherapy uses a radiotherapy machine that takes pictures during your treatment. The pictures show any movement of the tumour. Radiographers give the treatment when the tumour is in the correct position in the treatment area. It is sometimes called gating. 

4D radiotherapy is helpful for treating tumours in areas of the body that move during treatment. For example, these could be tumours in the lung that move as you breathe. The radiotherapy team use the information from the pictures to adjust the radiotherapy treatment area during treatment. 

There are other ways to help reduce movement in the treatment area. Your radiographer may show you some breathing techniques. Or they may use gentle compression on your tummy area, depending on where you are having treatment. They will do this during planning and treatment. It helps to reduce movement in the area being treated. This allows them to treat the area more accurately.

Stereotactic radiotherapy uses many small, focused beams of radiation. The beams are directed from different angles that meet at the tumour. This makes it very precise. It means very small areas of the body can get high doses of radiotherapy. This can reduce the risk of side effects. 

VMAT can also be used to give stereotactic radiotherapy. This means that the radiotherapy machine moves around you and reshapes the beam during treatment.

Stereotactic radiotherapy is used to treat different types of tumours. You may be offered this treatment as part of a clinical trial.

This treatment may not be available in all radiotherapy centres. Your radiotherapy team will give you more information if this treatment is suitable for the type of cancer you have.

TBI treatment is when a large single dose of radiation, or 6 to 8 smaller doses, is given to the whole body. This type of radiotherapy is not used very often. People who are having a stem cell transplant sometimes have it.

Proton beam therapy uses proton radiation rather than x-rays to destroy cancer cells. Proton beams stop when they reach the area being treated. This is different to standard radiotherapy beams, which pass through the area and some healthy tissue around it. Using proton beam therapy may help to reduce side effects and the risk of long-term effects.

Proton beam therapy is only suitable for a small number of people with certain types of cancer. It is available at:

• the Clatterbridge Cancer Centre in Wirral, to treat tumours of the eye
• the Christie Hospital in Manchester
• University College Hospital in London.

Some of these centres only recently began doing proton beam therapy. Until these treatment centres are fully operational, a small number of people who need this type of radiation may be able to have it abroad, paid for by the NHS

Your radiotherapy team will give you more information if proton beam therapy is suitable for you. You may have to travel to a hospital that offers it.

Intraoperative radiotherapy is when you have a single dose of radiation during surgery to remove a cancer. You have this in the operating theatre. This treatment is still being researched and may only be available in some centres as part of a clinical trial.

It may be an option in some situations. For example, it may be used for some people with early breast cancer who would normally have radiotherapy after surgery.

This treatment uses particles called electrons to give radiotherapy to the skin. It treats cancer on the skin or close to the skin surface. This type of radiotherapy does not travel far into your body. Your doctor will tell you if this is an option.