This is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. They work by disrupting the growth of cancer cells. Commonly used chemotherapy drugs to treat Kaposi's sarcoma are doxorubicin, vincristine (Oncovin®), bleomycin, etoposide (Etopophos®, Vepesid®) and paclitaxel (Taxol).

The chemotherapy drugs are usually given by drip (infusion) into a vein in your arm (intravenously), but some chemotherapy drugs can be taken as tablets (orally). They are then carried around the body by the bloodstream. Chemotherapy for KS is usually given every three weeks but may be given more frequently, depending on the drugs used. Treatment is often given as an outpatient.

If the KS is only affecting the skin, it may be possible to use chemotherapy injected directly into the skin lesion. This is known as intralesional chemotherapy and tends to be used for smaller lesions (less than 0.5cm (¼ inch) wide). It can be a useful alternative to radiotherapy for areas or skin types where radiotherapy might cause some darkening of the skin, particularly on the face. Intralesional chemotherapy can also be used for tumours inside the mouth.

For more extensive skin KS, chemotherapy is usually given as a drip into a vein.

Chemotherapy treatment can shrink the areas of Kaposi's sarcoma in the skin and make them lighter in colour. In some people the lesions may almost disappear completely.

A different form of chemotherapy, called liposomal chemotherapy, is now often used to treat KS. The molecules of the chemotherapy drugs are enclosed (encapsulated) in a fat-based coating known as a liposome. Liposomes are able to travel to the tumour site, where they release the drug. The advantage of this type of chemotherapy is that there are fewer side effects, which means that treatment can be given over a longer period.

The liposomal chemotherapy drugs that are commonly used to treat KS are liposomal daunoroubicin (Daunoxome®) and liposomal doxorubicin (Caelyx®, Myocet®). These drugs are usually given as drips (infusions) every 2–3 weeks.

Our section on chemotherapy discusses the treatment and its side effects in more detail. Information about individual drugs and their particular side effects are also available.

Chemotherapy can cause unpleasant side effects. However, many people have few side effects, and those that occur can often be well controlled with medicine. The main side effects are described here, along with some of the ways they can be reduced.

Lowered resistance to infection The chemotherapy can reduce the production of white blood cells by the bone marrow, making you more prone to infection. This is a common side effect of chemotherapy and usually begins seven days after treatment has been given. The number of white blood cells in your blood usually reaches its lowest point at 10–14 days after chemotherapy. Your blood cells will then increase steadily and will usually have returned to normal before your next course of chemotherapy is due.

Contact your doctor or the hospital straightaway if:

• Your temperature goes above 38ºC (100.5ºF)
• You suddenly feel unwell (even with a normal temperature).

You will have a blood test before having more chemotherapy, to make sure that your cells have recovered. Occasionally it may be necessary to delay your treatment if your blood count is still low.

Anaemia (low number of red blood cells) While having chemotherapy you may become anaemic. This may make you feel tired and breathless.

Bruising or bleeding The chemotherapy can also reduce the production of platelets, which help the blood to clot. Let your doctor know if you have any unexplained bruising or bleeding, such as nosebleeds, blood spots or rashes on the skin, and bleeding gums.

Nausea and vomiting Some of the drugs used to treat KS may cause nausea (feeling sick) and vomiting. There are now very effective anti-sickness drugs (anti-emetics) to prevent or reduce nausea and vomiting. Your doctor will prescribe these for you.

Hair loss Unfortunately, some chemotherapy drugs can make your hair fall out. You can ask your doctor if the drugs you are taking are likely to cause hair loss or other specific side effects.

People who lose their hair often wear wigs, hats or bandannas. Some people are entitled to a free wig from the NHS and your doctor or nurse will be able to give you more details. If your hair falls out, it will grow back within 3–6 months, once your treatment is over.

Sore mouth Some chemotherapy drugs can make your mouth sore and cause mouth ulcers. Regular mouthwashes can help to keep your mouth clean and relieve any soreness. Your nurse will show you how to use these properly. If you don’t feel like eating during treatment, you could try a diet of soft food or replacing some meals with nutritious drinks.

Skin reaction Intralessional chemotherapy may cause temporary inflammation of the skin.

Tiredness You may feel tired and have a general feeling of weakness. It is important to allow yourself plenty of time to rest.

Although they may be hard to bear at the time, these side effects will gradually disappear once your treatment is over.

Chemotherapy affects people in different ways. Some people find they are able to lead a fairly normal life during their treatment, but many find they become very tired and have to take things much more slowly. Just do as much as you feel like and try not to overdo it.