Radiotherapy treats cancer by using high-energy rays that destroy the cancer cells, while doing as little harm as possible to normal cells. It is not often used to treat chronic myeloid leukaemia, but is sometimes used if either your lymph nodes or spleen are very enlarged.

Radiotherapy is given in the hospital radiotherapy department and consists of daily treatments which each last a few minutes. The treatments are usually given from Monday to Friday, with a rest at the weekend. Radiotherapy treatment for CLL will usually be given for one or two weeks. You can usually have radiotherapy as an outpatient.

The side effects of radiotherapy will vary, depending on which part of the body is being treated. Radiotherapy to the spleen may make you feel sick (nauseated) or cause diarrhoea.

Our section on radiotherapy has further information about this treatment.