Kaposi sarcoma (KS) is a cancer that causes patches of abnormal tissue to grow under the skin, in the lining of the mouth, nose, and throat or in other organs. These patches are typically red or purple and are comprised of cancer cells and blood cells. If the cancer finds its way to the digestive tract or lungs, bleeding may occur. Lung tumours can make it difficult to breathe.
Before the HIV/AIDS epidemic, KS usually developed slowly. In HIV/AIDS patients, however, the disease moves quickly. Depending on where the lesions are and how severe they are, treatment may be different. Treatment for HIV itself can cause the lesions to shrink. Though, treating KS does not improve survival from HIV/AIDS.
Incidence of Kaposi sarcoma in SA, According to the National Cancer Registry (2014):
- 1 in 320 South African men will develop Kaposi sarcoma in their lifetime.
- 1 in 555 South African women will develop Kaposi sarcoma in their lifetime
Types of Kaposi Sarcoma
- Classic KS
- Usually very rare
- Usually found on the skin – mainly on the lower legs and feet
- Slow growing cancer which does not usually cause problems
- Should the lesions be large and in visible areas on the body, the patient may be given radiotherapy to get rid of it
- Doctor may also recommend freezing it with liquid nitrogen or removing it through a small operation
- Endemic or African KS
- Commonly found in parts of Africa, where HHV-8 infection is common
- Faster growing that Classic KS
- More common in men, however, women and children of all ages may develop it
- Transplant KS found in people with weakened immune systems
- People with weakened immune systems are most likely to develop this type
- AIDS-related KS
- Most common and fastest growing type of KS
- Should someone have AIDS, the immune system is weakened which increases the risk for developing KS
- Non-epidemic gay-related KS
- This rare type develops in active homosexual men who have no signs or symptoms of HIV infection
- Progression is slow with new lesions appearing every few years
- Lesions are commonly found on the arms, legs, and genitals, but are not limited to these areas
Signs and Symptoms
- The first symptoms are typically skin lesions
- Ranges in colour from pink to brown, brown-red, or reddish-purple
- May appear as a raised bump or a flat area on the skin
- Possible for more than lesion one to appear
- Any part of the skin can be infected, even the inside of the mouth
- Lymph nodes (glands)
- If the lymph nodes are affected by KS, the nodes may become swollen, but this normally causes few symptoms
- Swelling in the arms, legs and other places
- KS can lead to damaged lymph vessels
- When damaged, this may lead to a build-up of fluid in the arms or legs, called lymphoedema
- Severe swelling of the face and scrotum may also occur
- Lung problems
- KS in the lungs may cause breathlessness accompanied by a cough which may be life threatening
- Digestive system problems
- This includes the stomach and bowel
- Feeling nauseous and vomiting may also be caused by KS
- Patient may also experience difficulty eating and/or swallowing
- Lesions may bleed slowly on occasions, which over a period, may cause anaemia – low numbers of red blood cells
To be sure that a lesion is caused by KS, a doctor will usually take a small tissue sample from the lesion and send it to a laboratory for analysis. This process is called a biopsy. A specialist called a pathologist can often diagnose KS by looking at the cells in the biopsy sample under a microscope.
For skin lesions, the doctor may perform a punch biopsy, which removes a tiny round piece of tissue. If the complete lesion is removed, it is called an excisional biopsy. These procedures may often be done under local anaesthesia.
Lesions in other areas, including the lungs or intestines, can be biopsied during other procedures such as bronchoscopy or endoscopy.
Other tests may include:
- Oral examination
- To check for lesions on one’s palate, tongue, gums, or tonsils
- Rectal examination
- To check for lesions in the anus
- A procedure used to look at organs and tissues inside the body to check for abnormalities.
- A barium enema
- Used to track the progress of barium through the colon via X-rays
- Involves the use of an endoscope or sigmoidoscopy to view the lining of the rectum colon
- Chest X-rays
- To check for lung lesions
- Computed tomography (CT) imaging
- Looks for lesions or other abnormalities
- A procedure to check inside the trachea and large airways in the lungs for abnormal areas
- Inserted through the nose or mouth into the trachea and lungs
- Lung biopsy
- Should bronchoscopy reveal lesions in the lungs, the doctor may take a sample for microscopic examination
The following factors may lead to an increased risk of developing KS
- People of Jewish, Mediterranean and equatorial African descent have a greater risk of developing KS
- Men typically have a higher risk of developing KS than women
- Human herpes virus 8 (HHV-8)
- This virus may be the cause for KS to develop.
- Also called the Kaposi sarcoma herpes virus (KSHV)
- Immune deficiency
- Individuals with HIV/AIDS and those whose immune systems are suppressed due to organ transplantation have a higher risk of developing KS
- Sexual activity
- Active homosexual men tend to have a higher risk of HHV-8
Treatment of Kaposi sarcoma can be a challenge due to the immunosuppressed state of many of the people who are affected. These people have a high risk of infections from other procedures. Treatment may be recommended by the doctor based on the patient’s general health as well as on the location(s) of the lesions, how extensive they are, and how many they are in numbers.
Most cancers are typically treated by physical removal of the tumour or lesion, chemotherapy, radiation, or a combination. For people with AIDS, anti-HIV medications are used against the virus. This may lead to an improvement on the person’s overall health and help treat Kaposi sarcoma.
Some possible treatments for skin lesions are:
- Procedure that uses liquid nitrogen or other cryogens to freeze tissue.
- Locoregional therapy
- Locoregional therapy encompasses the injection of chemotherapy agents directly into the Kaposi sarcoma lesions
- Radiation therapy
- Direct radiation therapy may serve as another option for treating the lesions
- Involves aiming radiation directly at the spots
- Some side effects associated with radiation include fatigue
- Should the KS have advanced, and it affects the internal organs, other therapies may be prearranged
- Chemotherapy is an option for treating KS