Kaposi's Sarcoma

Kaposi's sarcoma is a cancer of vascular tissue. It is caused by a virus called human herpesvirus 8 (HHV-8). The tumors of Kaposi's sarcoma appear as red or purple patches or raised bumps (papules) on the skin, mouth, lungs, liver, and gastrointestinal tract.

There are 4 types of Kaposi's sarcoma:

  • Classic Kaposi's sarcoma: A rare, slow-growing skin tumor. It usually affects males of Italian or Eastern European Jewish ancestry.

  • African Kaposi's sarcoma: Occurs frequently among young males in certain countries in Equatorial Africa. Often, it is a slow-growing tumor. In some cases, the skin tumors invade bone and tissue under the skin.

  • Immunosuppressive treatment-related Kaposi's sarcoma: May develop in people who are taking immunosuppressive drugs after an organ transplant. It sometimes improves if the medicine is reduced or changed.

  • AIDS-related Kaposi's sarcoma: Affects people with late-stage HIV/AIDS. It is often a rapidly progressing tumor. It affects the skin, lymph nodes, gastrointestinal tract, lungs, liver, and spleen. The number of cases is decreasing due to highly active antiretroviral therapy (HAART) for HIV/AIDS.

CAUSES

It is believed that Kaposi's sarcoma is caused by or has a strong association with HHV-8. Exactly how this virus causes Kaposi's sarcoma is still being researched. Weakening of the body's natural defense system (immune system) appears to be a risk factor for developing Kaposi's sarcoma. Some causes of a weak immune system include:

  • Taking immunosuppressive drugs.

  • HIV.

  • Lymphoma.

SYMPTOMS

The first signs are often red, purple, or brown patches, plaques, or nodules on the skin. This often results in a bruise-like appearance.

In classic, African, and immunosuppressive treatment-related Kaposi's sarcoma:

  • Lesions often grow slowly and develop over years.

  • The lower legs may swell as the disease gets worse.

  • In some cases, the disease will spread to other organs.

In AIDS-related Kaposi's sarcoma:

  • The tumor grows rapidly. It often covers large areas, forming tumor-like masses. These tumors start out soft and spongy and often become hard over time. The tumor surface may form open ulcers. These ulcers may become infected.

  • This disease often affects the mouth, lymph nodes, lungs, liver, spleen, and gastrointestinal tract.

  • When the tumor involves the lungs, it often causes coughing, shortness of breath, and wheezing. The disease often progresses rapidly in the lungs. It can result in death from respiratory failure.

  • When the disease involves the bowel, it rarely causes problems. However, if the disease is very advanced, it may cause symptoms of intestinal obstruction (nausea, vomiting, abdominal pain) or bloody stools.

  • When the lymph nodes are involved, severe swelling of the legs or face can occur.

DIAGNOSIS

If your caregiver suspects Kaposi's sarcoma, he or she will ask about your medical history. If you do not know whether you are infected with HIV, your caregiver may recommend an HIV test. Kaposi's sarcoma can be confirmed by taking a tissue sample (biopsy). If you have Kaposi's sarcoma, your caregiver will try to determine how far it has spread by asking you questions and doing a physical exam.

PREVENTION

There is no way to prevent the milder forms of Kaposi's sarcoma. The most effective way to avoid AIDS-related Kaposi's sarcoma is to prevent the transmission of HIV. People who are HIV positive can decrease their risk of Kaposi's sarcoma by taking HAART.

TREATMENT

There is no cure for Kaposi's sarcoma. It is a lifelong condition. The goal of treatment is to ease symptoms, shrink the tumor, and prevent the disease from getting worse. The type of treatment advised depends on:

  • The type of Kaposi's sarcoma.

  • The size of the tumor.

  • Whether internal organs are involved.

  • Results of a test to measure the strength of your immune system (CD4 count).

  • Your general medical condition.

Treatments include:

  • Surgery to remove cancer cells.

  • Destroying cancer cells by freezing (cryotherapy).

  • Using cancer-fighting drugs (chemotherapy).

  • Using high-energy rays to kill or shrink tumors (radiation therapy).

  • Using the body's immune system to fight the cancer cells (biological therapy).

In people with AIDS, the lesions will improve with treatment of the AIDS itself. Typically, this involves antiretroviral medicines prescribed to improve the functioning of the immune system.

SEEK MEDICAL CARE IF:

  • You have skin changes that fit the description of Kaposi's sarcoma.

  • You have symptoms suggestive of HIV/AIDS, including:

  • Swollen lymph nodes.

  • Night sweats.

  • Fever.

  • Fatigue.

  • Weight loss.

FOR MORE INFORMATION

American Cancer Society: www.cancer.org

National Cancer Institute: www.cancer.gov