Kaposi's sarcoma (KS) is a type of cancer that usually affects the skin and mouth. KS can also affect organs inside the body such as the lungs, liver, stomach, bowel and lymph nodes (glands). It can appear in several parts of the body at the same time.
We hope this section answers your questions. If you have any further questions, you can ask your doctor or nurse at the hospital where you are having your treatment.
Causes of Kaposi's sarcoma
The main cause of KS is a virus called human herpes virus 8 (HHV8), which is also known as Kaposi’s sarcoma herpes virus (KSHV). Most people who have this virus never get KS. But people with a weakened immune system who have the virus are more likely to develop KS.
Our immune system is made up of tissues and organs that work together to protect us against infections. Different conditions can cause a weakened immune system. The one most commonly linked with KS is HIV (human immunodeficiency virus), the virus that can lead to Aids.
Types of Kaposi's sarcoma
There are four main types of KS and they are all more common in men than in women.
Epidemic or AIDS-related Kaposi's sarcoma
Epidemic KS is the most common of the four types. It’s associated with HIV infection, which can weaken a person’s immune system and increase their risk of getting KS if they also have HHV8.
KS is now less common because HIV is usually well controlled with treatment.
Classic Kaposi's sarcoma
Classic KS is rare. It’s more common in older men of Mediterranean, Middle Eastern or Jewish descent.
This type of KS is normally only found in the skin, particularly on the lower legs and feet. It’s a slow-growing cancer. People with early classic KS may not need treatment.
Endemic or African Kaposi's sarcoma
Endemic KS is found in parts of Africa where HHV8 is more common. It develops more quickly than classic KS and can affect men, women and children of all ages, although it’s more common in men.
Acquired Kaposi's sarcoma (sometimes called transplant Kaposi's sarcoma)
Rarely, people who have a weakened or damaged immune system after an organ transplant develop acquired KS. This is because they need to take drugs that suppress their immune system (immunosuppressants) to reduce the risk of rejecting the donated organ.
Symptoms and diagnosis of Kaposi's Sarcoma
If you are worried about Kaposi's sarcoma, you should speak to your specialist or PCP.
Signs and symptoms of Kaposi's sarcoma
The first symptom of Kaposi’s sarcoma (KS) is usually skin lesions. Occasionally, KS can also affect other parts of the body such as the lungs, liver, stomach, bowel and lymph nodes (glands). When this happens, the symptoms will depend on the part of the body that’s affected. Some people may have general symptoms such as fever, weight loss and loss of energy.
These can range in color from pink to brown, brown-red or reddish purple. KS can appear as a raised or slightly raised bump (nodule) or a flat area on the skin.
The lesions can develop quickly. Although there may be a single area at first, it’s possible for more than one to appear. Often the lesions merge to form a larger tumor. Any part of the skin can be affected, including the inside of the mouth.
Lymph nodes (glands)
If the lymph nodes are affected by KS, they may become swollen but this generally causes few symptoms.
Swelling in the arms and legs
KS can cause damage to lymph vessels. These are part of our lymphatic system, which helps us fight infection. When the lymph vessels are damaged, this can lead to a build-up of fluid in the arms or legs. This is called lymphoedema.
KS in the lungs can cause breathlessness and a cough.
Digestive system (stomach and bowel) problems
KS may cause symptoms such as feeling sick (nausea) and being sick (vomiting).
Occasionally the lesions may bleed slowly, which over a period of time may cause anemia (low numbers of red blood cells).
How Kaposi's sarcoma is diagnosed
If you have been diagnosed with HIV, your HIV specialist will usually arrange for you to have your symptoms investigated. However, some people may go to their PCP with symptoms and will then be referred to a specialist for tests.
If you’re diagnosed with KS but haven’t been tested for HIV, your doctor will discuss testing with you. Knowing whether you have HIV or not will determine how the KS is treated.
Your specialist may suspect you have KS just by looking at the skin lesions, but you’ll usually need a biopsy to confirm the diagnosis.
This is usually a quick procedure that can be done in an outpatient department. Your doctor will remove a small piece of the lesion, which will then be examined under a microscope. The area may be sore for a few days, so you may need to take some painkillers.
If the biopsy results show that you have KS, but you don’t have any other symptoms, you may not need any further tests.
You may have further tests if your specialist wants to make sure that there is no KS elsewhere in your body. There are a number of different tests that can be done. Your doctor will explain more about the tests you need and why they’re the most appropriate for you.
Tests can include using a thin fiber-optic tube to look at, and take biopsies of, the inside of the lungs (called a bronchoscopy) or the gullet and stomach (called an endoscopy). You may also have a CT scan.
CT (computerized tomography) scan
A CT scan takes a series of x-rays that build up a three-dimensional picture of the inside of the body. The scan is painless and takes 10–30 minutes. It can help show whether there are any signs of KS in other parts of the body. CT scans use small amounts of radiation, which will be very unlikely to harm you or anyone you come into contact with.
You’ll be asked not to eat or drink for at least four hours before the scan.
You may be given a drink or injection of a dye that allows particular areas to be seen more clearly. This may make you feel hot all over for a few minutes. If you’re allergic to iodine or have asthma, you could have a more serious reaction to the injection, so it’s important to let your doctor know beforehand.