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Kaposi Sarcoma

(Kaposi's Sarcoma; Multiple Idiopathic Hemorrhagic Sarcoma)


Vinod E. Nambudiri

, MD, MBA, EdM, Harvard Medical School

Reviewed/Revised Jan 2024
Topic Resources
  • One or a few spots may appear on the toes or a leg, or spots may appear anywhere on the body or in the mouth or genital areas, then spread to other areas, including internal organs.

  • Although this cancer can often be identified by sight, doctors usually also do a biopsy.

  • Spots may be removed or treated with radiation therapy, but if the cancer is aggressive, treatment includes chemotherapy or interferon alfa.

There are 5 types of Kaposi sarcoma. The types occur in several distinct groups of people and act differently in each group. It occurs in the following:

Symptoms of Kaposi Sarcoma

Kaposi sarcoma usually appears as purple, pink, brown, or red spots or bumps on the skin. The cancer may grow to several inches or more as blue-violet to black, flat or slightly raised areas. Swelling may be present. Sometimes the cancer grows deeper into soft tissues and invades bone.

Cancer of mucosal surfaces, such as in the mouth, are blue to violet in color. In the digestive tract, the cancer can sometimes bleed excessively but usually causes no symptoms.

Classic Kaposi sarcoma

Men over age 60 with the classic type may develop several additional spots on the legs, but the cancer rarely spreads to other parts of the body and is almost never fatal.

In the 4 other types of Kaposi sarcoma, the cancer may be more aggressive. Similar-appearing spots develop, but they are often multiple and may occur anywhere on the body.

AIDS-associated Kaposi sarcoma

Within several months, people with the AIDS-associated type develop spots that spread to other parts of the body, such as the face and torso, often including the mouth, where they cause pain with eating.

The spots may also develop in lymph nodes and internal organs, especially the digestive tract, where they can cause internal bleeding that leads to blood in the stool. Sometimes Kaposi sarcoma is the first symptom of AIDS.

Did You Know...

  • In the United States, most cases of Kaposi sarcoma occur in people with AIDS.

Iatrogenic Kaposi sarcoma (immunosuppressive Kaposi sarcoma)

This type typically develops several years after organ transplantation. It can be severe, and spots may rapidly develop.

Endemic Kaposi sarcoma

In children, the endemic type usually involves the lymph nodes. The children may or may not have spots on the skin. The disease is usually sudden, severe, and fatal.

In adults, the endemic type tends to cause slow-growing spots and patches on the skin similar to those of the classic type. The cancer rarely spreads to other parts of the body and is not likely to be fatal.

Non-epidemic Kaposi sarcoma

This recently described type typically manifests with individual spots similar to classic Kaposi sarcoma, but it occurs specifically in men who are HIV-negative and who have sex with men. The severity of this type is still being studied.

Diagnosis of Kaposi Sarcoma

  • Punch biopsy

Doctors diagnose Kaposi sarcoma by doing a punch biopsy Biopsy Doctors can identify many skin disorders simply by looking at the skin. A full skin examination includes examination of the scalp, nails, and mucous membranes. Sometimes the doctor uses a hand-held... read more Biopsy , in which a small piece of skin is removed for examination under a microscope, is usually done to confirm the diagnosis of Kaposi sarcoma.

For people with AIDS or immunosuppression, doctors do other tests to determine where the cancer has spread. Doctors usually do a computed tomography (CT) scan of the chest and the abdomen and do other tests depending on the person's symptoms.

Treatment of Kaposi Sarcoma

  • For people with one or two spots, various removal methods

  • For people with many spots, many affected areas, or affected lymph nodes, radiation therapy and chemotherapy

  • For the AIDS-associated type, antiretroviral medications and removal methods or antiretroviral medications and chemotherapy

Treatment varies depending on the type of sarcoma.

Classic Kaposi sarcoma

Older men with slow-growing classic Kaposi sarcoma in one or two spots may have the tumors removed surgically, with extreme cold (cryosurgery), or with an electrical current (electrocoagulation). Imiquimod cream, alitretinoin gel, or injections of vinblastine or interferon alfa into the spots may also be used to remove the spots. Some people with very few spots and no other symptoms may choose to receive no treatment unless the condition spreads.

Iatrogenic Kaposi sarcoma

In people taking immunosuppressant medications, the tumors sometimes disappear when immunosuppressant medications are stopped. However, if these medications must be continued because of the person’s underlying condition, the dose is reduced. If the dose of immunosuppressants cannot be reduced, surgery, chemotherapy, and radiation therapy are used. People may also be given an immunosuppressant medication called sirolimus. These treatment methods are less successful than in people with a healthy immune system.

AIDS-associated Kaposi sarcoma

In people with AIDS, treatment with chemotherapy and radiation has not been very successful. However, intensive treatment with antiretroviral therapy Antiretroviral Treatment of Human Immunodeficiency Virus (HIV) Infection Antiretroviral medications used to treat human immunodeficiency virus (HIV) infection aim to do the following: Reduce the amount of HIV RNA (viral load) in the blood to an undetectable amount... read more (ART) helps. Some people who have the AIDS-associated type need only ART and the removal methods noted above. Other people who have the AIDS-associated type may need chemotherapy (such as doxorubicin or paclitaxel) by vein or other medications (such as vinblastine or pomalidomide) in addition to ART. In general, treating Kaposi sarcoma does not prolong the lives of most people with AIDS.

Endemic Kaposi sarcoma

The endemic type is difficult to treat. Doctors typically make sure people are comfortable and free of pain and that their symptoms are fully treated.

Non-epidemic Kaposi sarcoma

Spots that appear in people who have this type of sarcoma are treated the same way as in classic Kaposi sarcoma Classic Kaposi sarcoma Classic Kaposi sarcoma .

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Aldara, Zyclara
HYFTOR, Rapamune
Adriamycin, Adriamycin PFS, Adriamycin RDF, Rubex
Onxol , Taxol
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