Kaposi’s sarcoma (KS) results in purplish-black lesions on the skin, mucous membranes or internal organs. It can affect people at all stages of HIV infection, as well as some HIV-negative people, and it is unlikely to be serious as long as the CD4 cell count is above 250. People with lower CD4 counts are more likely to develop KS that affects internal organs, such as the lymph nodes or lungs, with potentially life-threatening consequences.
KS is now believed to be caused by a virus called human herpes virus 8 (HHV-8), which is also known as Kaposi’s sarcoma-associated herpes virus (KSHV). In the presence of other factors such as immune suppression or other effects of HIV in the body, HHV-8 is thought to encourage normal cells to change into tumor cells.
Both HHV-8 and Kaposi’s sarcoma itself are much more common among HIV-positive gay or bisexual men, women infected by bisexual men, and people from African communities, than other groups of people with HIV. Earlier ideas about the cause of KS, such as the theory that it was linked to the recreational use of poppers (inhaled nitrites) by gay men, have now been discounted.
HHV-8 appears to be sexually transmitted, although it could also be transmitted in other ways. There is no generally available test for HHV-8 yet; a test might not be useful anyway since no one knows what proportion of HIV-positive people infected with HHV-8 will go on to develop KS.
The best way to diagnose KS is by taking a sample from a skin lesion. Experienced doctors may diagnose KS simply by looking at it. KS inside the body can often be detected using X-rays and fiber-optic viewing instruments. You and your doctor may decide not to treat your KS if you only have a few lesions on the skin, if your CD4 count is high and if the lesions are not causing you significant distress or embarrassment. Some AIDS centers or organizations like the Red Cross may be able to advise you about ways of camouflaging lesions using cosmetics.
However, over time KS generally progresses and spreads if left untreated. Doctors will normally recommend treating poor prognosis KS (i.e. KS that is likely to develop rapidly), for example, when there are many lesions, when they affect internal organs, or when your CD4 count is low.
In many cases, the best initial approach to treating KS may be to inhibit HIV and boost the immune system using a strong combination of anti-HIV drugs. Like most other opportunistic infections, there have been many reports of people whose KS improved or disappeared once they started taking protease inhibitor-based combinations. Encouraging evidence that triple NRTI combinations and combinations including an NNRTI have an equally powerful effect on KS has recently emerged.
There is also a range of specific KS treatments. If the KS only affects your skin, you may be able to use `topical’ therapies such as gels or creams, localized radiation therapy, injections of chemotherapy drugs into the lesions, or methods that freeze or burn them.
For more extensive KS, you may be advised to consider `systemic’ treatments that affect the whole body, such as injections of chemotherapy drugs or interferon. Liposomal drugs are just as effective but significantly less toxic than standard chemotherapy drugs.
In the future, drugs that inhibit HHV-8 may be used to treat KS. However, they might not be effective against KS lesions that have already formed. For example, some lymphomas are caused by the common virus EBV, but anti-EBV drugs seem not to be effective against lymphomas once they have started to grow.
Conditions that suggest Kaposi's Sarcoma
AIDS / Risk
People with AIDS are particularly prone to developing various cancers, especially those caused by viruses such as Kaposi’s sarcoma, cervical cancer or cancers of the immune system known as lymphomas. Kaposi’s sarcoma is often a late stage complication of AIDS which carries a poor prognosis.
Kaposi's Sarcoma suggests the following may be present
AIDS / Risk
People with AIDS are particularly prone to developing various cancers, especially those caused by viruses such as Kaposi’s sarcoma, cervical cancer or cancers of the immune system known as lymphomas. Kaposi’s sarcoma is often a late stage complication of AIDS which carries a poor prognosis.
Recommendations for Kaposi's Sarcoma
Vitamin C (Ascorbic Acid)
Some doctors recommend large amounts of vitamin C for people with AIDS. Reported benefits in preliminary research using 40 to 185gm per day include greater resistance against infection and an improvement in overall well-being. Use of such high doses should be monitoered by a doctor. This same researcher also reports some success in using a topical vitamin C paste to treat herpes simplex outbreaks and Kaposi’s sarcoma in people with AIDS. [Med Hypotheses 1984;14: pp.423-33]
Key
| Weak or unproven link |
| Strong or generally accepted link |
| May do some good |
Glossary
Mucous Membranes
The membranes, such as the mouse, nose, anus, and vagina, that line the cavities and canals of the body which communicate with the air.
HIV
Abbreviation for human immunodeficiency virus, a retrovirus associated with onset of advanced immunodeficiency syndrome (AIDS).
CD4
A symbol for glycoprotein expressed on the surface of some lymphocytes, including Helper T cells. Human CD4 is the receptor that serves as a docking site for HIV viruses on certain lymphocyte cells. Binding of the viral glycoprotein gp120 to CD4 is the first step in viral entry, leading to the fusion of viral and cell membrane. In a healthy adult, helper T-cells account for between 32% and 68% of the total number of lymphocytes (which includes B-cells and other types of T-cells). The CD4 percentage is sometimes a more reliable measurement than the CD4 count because it tends to vary less between measurements. For example, one person's CD4 count may vary between 160 and 240 over a period of several months while their CD4 percentage remains constant at, say, 15%. The reason for this is that the CD4 count isn't actually a direct count of CD4 cells, but rather a calculation based on the results of three other tests (the CD4 percentage, the lymphocyte percentage, and the WBC count), each of which can vary slightly each time it's measured. Occasionally the CD4 count may be relatively high while the CD4 percentage is low (less than 21%). In this situation, many healthcare providers would consider the immune system to be significantly impaired based on the CD4 percentage.
Lymph Nodes
Small, bean-shaped nodes at various points throughout the body that function to filter the lymph fluid and attempt to destroy the microorganisms and abnormal cells which collect there. The most common locations are the neck (both sides and front), armpit and groin, but also under the jaw and behind the ears. Swollen or painful lymph nodes generally result from localized or systemic infection, abscess formation, or malignancy. Other causes of enlarged lymph nodes are extremely rare. Physical examination for lymph nodes includes pressing on them to check for size, texture, warmth, tenderness and mobility. Most lymph nodes can not be felt until they become swollen, and then will only be tender when pressed or massaged. A lymph node that is painful even without touching indicates greater swelling. Lymph nodes can usually be distinguished from other growths because they generally feel small, smooth, round or oval-shaped and somewhat mobile when attempts are made to push them sideways. Because less fat covers the lymph nodes in children, they are easier to feel, even when they are not busy filtering germs or making antibodies. Children’s nodes enlarge faster, get bigger in response to an infection and stay swollen longer than an adult's.
Virus
Any of a vast group of minute structures composed of a protein coat and a core of DNA and/or RNA that reproduces in the cells of the infected host. Capable of infecting all animals and plants, causing devastating disease in immunocompromised individuals. Viruses are not affected by antibiotics, and are completely dependent upon the cells of the infected host for the ability to reproduce.
Immune System
A complex that protects the body from disease organisms and other foreign bodies. The system includes the humoral immune response and the cell-mediated response. The immune system also protects the body from invasion by making local barriers and inflammation.
Chemotherapy
A treatment of disease by any chemicals. Used most often to refer to the chemical treatments used to combat cancer cells.
Interferon
A protein formed by the cells of the immune system in the presence of a virus, etc. It prevents viral reproduction, and is capable of protecting noninfected cells from viral infection. Several kinds of interferon exist including alpha, beta, and gamma.
Epstein Barr virus
(EBV): A virus that causes infectious mononucleosis and that is possibly capable of causing other diseases in immunocompromised hosts.
Cancer
Refers to the various types of malignant neoplasms that contain cells growing out of control and invading adjacent tissues, which may metastasize to distant tissues.