Radiotherapy treats cancer by using high-energy x-rays to destroy as many cancer cells as possible, while doing as little harm as possible to normal cells.

Radiotherapy is used less often than surgery or chemotherapy. It is sometimes used to treat cancer of the pancreas which has not spread but can’t be removed by surgery. In this situation it may be used together with chemotherapy (known as chemoradiation) to shrink the cancer and keep it under control for as long as possible.

Radiotherapy is also sometimes given to relieve symptoms such as pain. The radiotherapy can shrink the tumour and so relieve pressure which may be causing pain. The dose of radiotherapy used to relieve symptoms is usually lower so you may have a shorter course of treatment and less chance of side effects.

Radiotherapy is given in the hospital radiotherapy department. How the treatment is given can vary a lot, depending on your particular needs. Sometimes a single treatment is all that is needed, but usually a course of therapy is given in daily sessions from Monday–Friday, with a rest at the weekends. Each session lasts only a few minutes. The course of treatment may last for a number of weeks. Your doctor will discuss your treatment with you in detail beforehand.

To ensure that you receive maximum benefit from your radiotherapy, it has to be carefully planned. This is done using a CT scanner, which takes x-rays of the area to be treated. Treatment planning is a very important part of radiotherapy and it may take a few visits to complete.

Marks may be drawn on your skin to help the radiographer, who gives you your treatment, to position you accurately and to show where the rays are to be directed. These marks must stay visible throughout your treatment, but they can be washed off once it is over. At the beginning of your radiotherapy you will be told how to look after the skin in the area to be treated.

Before each session of radiotherapy the radiographer will position you carefully on the couch, either sitting or lying, and make sure that you are comfortable. During your treatment, which only takes a few minutes, you will be left alone in the room, but you will be able to talk to the radiographer, who will be watching you carefully from the next room. Radiotherapy is not painful but you have to be still for a few minutes while your treatment is being given.

Radiotherapy for cancer of the pancreas can cause side effects such as feeling sick (nausea), vomiting, diarrhoea and tiredness. These side effects can be mild, or more troublesome, depending on how much treatment you are having. Your cancer specialist will be able to advise you what to expect.

Our radiotherapy section tells you more about this treatment and its side effects.