Radiotherapy is a treatment which uses high-energy rays to destroy the Kaposi's sarcoma cells while doing as little harm as possible to normal cells. The radiotherapy is aimed at the skin lesions or internal tumours and is painless. Usually between one and five doses are given.

After radiotherapy to the skin, small lesions may fade completely but larger and deeper lumps may become smaller and flatter, similar to a mole. Radiotherapy can be very effective in reducing symptoms of internal KS, particularly swelling, pain and bleeding.

Side effects

Skin care Side effects of radiotherapy depend on the area of the body which is being treated. Radiotherapy to the skin alone usually causes few side effects. Pale skin around the treated area may become red, sore and itchy. People with darker skins may develop a blue or black tinge in the treated area. Advice about skin care varies from one hospital to another. Some will advise you not to wash the skin at all while you are having radiotherapy. Others will advise you to use only tepid water on the area and to pat it dry with a soft towel. Perfumed creams and lotions should be avoided and you should check with the radiotherapy staff before applying anything to your skin.

If necessary, your doctor will prescribe a special cream to soothe the sore area. Avoid exposing the treated area to the sun or extremes of hot or cold.

Hair loss Radiotherapy may make your hair fall out in the treated area. Hair in other areas of the body is not affected. Your hair may grow back once your treatment is over, but in some cases the hair loss may be permanent.

Feeling sick Radiotherapy to tumours in or near the digestive system can lead to nausea and vomiting. Anti-sickness (anti-emetic) drugs can often help to overcome this problem. It can also help if you avoid large meals and eat small amounts more often, or supplement your diet with nutritious drinks, which you can buy at most chemists.

Hoarse voice Radiotherapy near the voice box (larynx) may cause hoarseness of the voice. This is usually temporary and should begin to reduce once the treatment has finished.

Tiredness You may feel very tired. It is important to get as much rest as possible, especially if you are travelling a long way for treatment every day.

Most side effects of radiotherapy disappear gradually once your course of treatment is over, although some may continue for several months afterwards. If you have any problems during your treatment, talk to the radiotherapy staff at the hospital, as they have experience of looking after other people in the same situation as yourself.

Radiotherapy does not make you radioactive and it is perfectly safe for you to be with other people, including children, throughout your treatment.