This form of skin cancer has been linked with infectious diseases.
Kaposi sarcoma (KS) is a form of skin cancer in which malignant tumors form in the skin, mucous membranes, lymph nodes, and other organs.
KS causes lesions that may appear reddish or purple in color.
KS is different from other skin cancers in that these lesions often appear in more than one place on the body simultaneously.
All KS lesions contain human herpesvirus-8 (HHV-8). This virus is also called Kaposi sarcoma herpes virus (KSHV).
Most people infected with HHV-8 do not get KS. However, those who have HHV-8 and are at highest risk for KS include those with compromised immune systems due to disease, medications, or organ transplant.
There are several types of KS:
If you are diagnosed with KS, your prognosis may depend on the type of KS you have, as well as your overall health and whether your cancer is new or recurring.
Over the past 30-plus years, KS has been associated with HIV/AIDS, since people with AIDS often develop the cancer as a result of their weakened immune systems.
In people who do not have HIV/AIDS, KS tends to progress relatively slowly.
However, in people with HIV/AIDS, the disease progresses rapidly and is generally much more serious.
KS lesions on the skin are typically purple, red, or brown. They can be categorized as:
KS lesions most often develop on the legs or face, but they can also appear in other areas.
Symptoms depend on the location of the lesions. For example:
Occasionally, KS lesions bleed, resulting in:
There are multiple treatments for KS.
If you have HIV/AIDS, your treatment will most likely focus on slowing the progression of that virus, which will also slow the progression of KS.
Controlling KS requires keeping the immune system as healthy and strong as possible, and treating any infections that develop.
Other KS treatments used for people who do not have HIV/AIDS include:
There are several surgical procedures that can be used to treat KS.
Your surgeon may perform a local excision, cutting the cancerous lesion from the skin along with an area of normal tissue around it to ensure that all of the cancer cells are removed.
Another option is electrodesiccation and curettage (ED&C), in which a surgeon removes the surface of the skin cancer with a scraping instrument (curette) and then sears the base with an electric needle.
Your doctor may also recommend killing the KS cells by freezing them using liquid nitrogen. This is sometimes called cryosurgery.
Chemotherapy is also used in the treatment of KS.
Anticancer drugs may be injected directly into the lesions (intralesional chemotherapy), or applied directly to the surface of the lesions (topical chemotherapy).
Another option is liposomal chemotherapy, in which fat particles (liposomes) are used to carry an anticancer drug (doxorubicin) to KS lesions.
The liposomes accumulate in KS lesions more than in healthy tissue, and the drug is released slowly, increasing its effect while causing less damage to healthy tissue.
Some of the chemotherapy drugs approved by the Food and Drug Administration (FDA) for the treatment of KS include:
Biologic therapy with interferon alfa is also used to treat KS, as is targeted therapy, which uses drugs or other substances to identify and attack specific cancer cells without harming normal cells.
Monoclonal antibody therapy with bevacizumab is one type of targeted therapy being studied for the treatment of KS.
Finally, in radiation therapy, a doctor uses high-energy beams (usually X-rays) to kill cancer cells.