Kaposi's sarcoma is type of cancer that can affect the skin and internal organs. Extremely rare, it is caused by a virus, and is mainly seen in people with a severe HIV infection. It can also affect some people who have a weakened immune system for other reasons, as well as people who have a genetic vulnerability to the virus.
The virus that causes Kaposi's sarcoma is called HHV-8 (human herpesvirus). It is a relatively common virus and the vast majority of people who have it will not develop Kaposi's sarcoma. It only seems to cause cancer in some people with a weak immune system and in some people who have a genetic vulnerability to the virus. It is thought to be spread during sex, through saliva, or from a mother to her baby during birth.
The most common first symptom is the appearance of small, painless, flat patches on the skin or inside the mouth. They're usually red or purple, a little like bruises. Over time, these patches can grow into nodules (small lumps) and may merge into each other. The internal organs can also be affected, including the lymph nodes, lungs and the digestive system. Symptoms include:
- Uncomfortable swelling in the arms or legs (lymphoedema).
- Breathlessness, chest pain and coughing up blood.
- Nausea, vomiting, stomach pain and diarrhoea.
Without treatment, symptoms will rapidly (over weeks or months) worsen, but they can also progress very slowly over many years.
With proper treatment, Kaposi's sarcoma can usually be controlled for many years. Deaths from the condition are uncommon in the UK. However, a complete cure isn't always possible, and there's a chance the condition could recur in the future. If you think this is happening, contact your HIV clinic, hospital specialist or GP as soon as possible.