Kaposi’s Sarcoma

Kaposi’s sarcoma is a cancer that causes dark, reddish spots under the skin. The spots are made up of a tangled knot of blood vessels. They can show up in the mouth, nose, throat, internal organs or anywhere else on the body.

Kaposi’s sarcoma was once thought to be a rare disease. It mainly affected older men of Mediterranean, African or Jewish descent. It also affected people who had had an organ transplant and were taking drugs to prevent rejection of the new organ.

In the early 1980s, an aggressive form began to be seen in AIDS patients. This was one of the first clues about the AIDS epidemic.
Kaposi’s sarcoma affects about one out of every five people with AIDS who aren’t taking anti-HIV drugs. With strong antiretroviral therapy, many fewer people get Kaposi’s sarcoma. It can affect people at all stages of HIV infection.

Symptoms

The signs of Kaposi’s sarcoma vary and can include:

• Red, purple, brown or black spots. Usually painless, they sometimes swell and hurt.
• The spots most often are found under the skin or on moist tissues such as the mouth, nose, throat or eye. They may also be found on the lungs, liver, stomach, intestines or lymph nodes. The spots can be dangerous if they swell enough to block breathing, eating or the flow of blood. Spots that bleed inside the body can be fatal.
• Difficulty walking, if the spots are on the legs and feet
• Swelling or puffiness of the arms, legs, face or scrotum if the spots block the lymph nodes
• A serious cough, shortness of breath and fluid in the lungs, if the spots are in the lungs.
• Fever, weight loss, or diarrhea

In the later stages of Kaposi's sarcoma, life-threatening infections are common. Eventually, without treatment, Kaposi’s sarcoma spreads throughout the body. 

Causes and Risk Factors

Kaposi’s sarcoma is a caused by a herpes virus. Most people who are infected never get Kaposi’s sarcoma. People who have weakened immune systems can’t keep the virus in check.

Kaposi’s sarcoma is usually not serious as long as the CD4 cell count is above 250. People with lower CD4 counts are more likely to develop Kaposi’s sarcoma that affects internal organs, such as the lymph nodes or lungs. This can be life threatening.

The disease affects men more than women. There are at least eight men with Kaposi’s sarcoma for every woman who has it.

Prevention

There are blood tests to detect antibodies against HIV-related Kaposi’s sarcoma. These can help determine if a patient is at risk for transmitting infection to his or her sexual partner.

It is not clear how the virus that causes Kaposi’s sarcoma spreads. It might happen from sex or deep kissing. The best way to prevent Kaposi’s sarcoma is to use strong anti-HIV drugs to keep the immune system strong.

Diagnosis

Kaposi's sarcoma is sometimes discovered during a regular dental check-up. If it is on the skin, it is easy to see.

A doctor will ask questions about the patient’s medical history and do a physical exam. He or she can often diagnose Kaposi’s sarcoma by how it looks. The spots on the skin are usually flat, painless, don’t itch and don’t drain. They look like bruises. If the spots are pressed, they don’t lose their color the way a bruise does.

The doctor may take a sample to look at under a microscope. This is called a biopsy. The tumor cells of Kaposi’s sarcoma have a long, spindle-like shape. There is also a viral protein (LANA) in the cells. This will confirm the presence of Kaposi’s sarcoma.

Other tests that may be done include:

• A chest X-ray to see if the lungs are affected
• An examination with an endoscope. This is a thin, tube with a light and a lens. It can be put inside the body through the mouth or other opening such as an incision (cut) in the skin. It may have a tool to take tissue samples. This lets the doctor check for signs of disease.
• An examination of the windpipe (trachea) and large airways of the lungs using a bronchoscope. A bronchoscope is like an endoscope that is used to look inside the lungs.

When a person with HIV is diagnosed as having Kaposi’s sarcoma, it means he or she has AIDS.

Treatment

It isn’t possible to cure Kaposi’s sarcoma. It can be treated so the symptoms go away or become weaker. Strengthening the immune system is the best treatment. Antiretroviral therapy can clear up the spots or stop their growth.

Kaposi's sarcoma can be treated by:

• Using the body’s immune system to fight the cancer. Materials made by the body or in a lab help boost, direct or restore the body’s natural defenses against diseases. Sometimes this is called biological response modifier (BRM) therapy or immunotherapy.
• Chemotherapy. This uses drugs to kill the cancer. The drugs can be given either in a pill form or as a shot.
• Radiation therapy. This uses high doses of X-rays or other high-energy rays to kill the cancer cells and shrink the tumors.
• Surgery. This removes the tumor from the body. The tumor can be cut away, killed by burning and then removed or frozen with liquid nitrogen.

Several drugs may be used if internal organs are affected by Kaposi’s sarcoma. These include:

• Doxorubicin (Doxil®). This, like daunorubicin is an anti-cancer drug wrapped in a small bubble of fat (a liposome). Liposomal drugs last longer than other forms. They move to the areas where they are most needed. Some side effects are less with these types of drugs.
• Daunorubicin (DaunoXome®) or
• Paclitaxel (Taxol®)

It may not be necessary to treat Kaposi’s sarcoma if:

• There only a few spots on the skin
• The spots don’t cause the patient distress or embarrassment, and
• The patient’s CD4 count is high

Sometimes creams or gels put on the skin help.

Usually, however, Kaposi’s sarcoma progress and spreads without treatment.  Treatment is recommended when there are many spots, internal organs are affected or the patient’s CD4 count is low.
 
The best approach to treating Kaposi’s sarcoma is to inhibit HIV and boost the immune system using anti-HIV drugs. Protease-inhibitor-based drug combinations often help. Triple NRTI combinations and ones including an NNRTI have also shown promise.