What are HIV and AIDS?

Certain types of cancer occur so often in people with AIDS that they are considered AIDS-defining conditions – that is, their presence in a person infected with HIV is a clear sign that full-blown AIDS has developed. They are also called AIDS-related cancers and include the following:

• Kaposi sarcoma
• Lymphoma (especially non-Hodgkin lymphoma and primary central nervous system lymphoma)
• Invasive cervical cancer

Other types of cancer that may be more likely to develop in people with HIV infection are anal cancer, Hodgkin disease, lung cancer, cancer of the mouth, cancer of the testicles, and skin cancers. Of course, people without HIV or AIDS can also have all of these types of cancer, even the ones that are better known as AIDS-related. They are only called AIDS-related cancers if they develop in people with HIV infection.

In developed countries like the United States, about 4 people in 10 with AIDS develop cancer at some time during their illness. But the cancer picture in HIV is changing. Kaposi sarcoma and non-Hodgkin lymphoma have decreased as anti-HIV treatment has become more common. Effective anti-HIV treatment is one of the reasons for the decrease in some types of cancer among those with HIV.

Some types of cancer do not seem to be slowed by HIV treatment, and have the same risk factors as those in people without HIV. For instance, people who smoke and have HIV are more likely to have cancers of the lip, mouth, throat, and lung than people who have HIV and don't smoke.

The relationship between HIV and these other cancers is still not fully understood. For some cancers, the higher risk in people who have HIV may be related to risk factors these people are more likely to have (such as smoking) rather than to the HIV infection itself. But some cancers may be able to develop and grow more quickly because people with HIV have weaker immune systems than those without HIV.

Weaker immune systems can also make cancers harder to treat. For instance, HIV infection can damage the bone marrow (which is needed to make new blood cells). People with bone marrow damage may have more serious risks from chemotherapy, such as an increased risk of infection.

For those who get cancer, anti-HIV drugs have led to better survival with anti-cancer treatment. Anti-HIV drugs also allow many people with cancer to get full doses of chemotherapy and other standard cancer treatment.

AIDS-related Kaposi sarcoma

Kaposi sarcoma (KS) was once an uncommon cancer that mainly affected older men of Mediterranean or Jewish ancestry, organ transplant patients, or young men in Africa. This form is called classic KS or endemic KS. However, in the 1970s and 80s the number of people with KS increased dramatically.

In the past 30 years, most KS cases in the United States have been linked to HIV infection in men who have sex with men. These cases are called epidemic KS. It is now known that KS in people with HIV is related to a second viral infection. This virus is called human herpes virus 8 (HHV-8), also known as Kaposi sarcoma-associated herpes virus (KSHV). HHV-8 does not appear to cause disease in most healthy people. Infection with HHV-8 is common in the United States among men who have sex with men, but it can also be shared through sex between men and women. The virus is found in saliva, which may be one of the ways it is passed to others.

In most cases, epidemic KS causes dark purplish or brownish spots (called lesions) that can show up on or inside the body. The spots may be seen on the skin or in the mouth. KS may also affect the lymph nodes and other organs, such as the digestive tract, lung, liver, and spleen.

When they are first diagnosed, some people with HIV and KS have no other symptoms, especially if their only lesions are on the skin. But many – even those with no skin lesions – have swollen lymph nodes, unexplained fever, or weight loss. Over time, epidemic KS spreads throughout the body. If KS involves a lot of the lung or intestine, it can be fatal.

In general, people who are diagnosed with epidemic KS are started on anti-HIV drugs, and often get treatment directed at the cancer itself. For more information about KS and its treatment, please see our document, Kaposi Sarcoma.

Lymphomas

Non-Hodgkin lymphoma (NHL) can occur in up to 4% to 10% of people with AIDS. It is a cancer that starts in lymphoid tissue and may spread to other organs. People who have had high viral loads and low T cell counts are more likely to get this type of cancer. Fewer HIV-infected people are developing lymphoma since anti-HIV drugs have been in common use.

There are many different types of non-Hodgkin lymphoma, but certain types are more common in people with AIDS. One of these is primary central nervous system (CNS) lymphoma, which starts in the brain or spinal cord. Symptoms of CNS lymphoma can include seizures, facial paralysis, confusion, memory loss, and lethargy (tiredness). AIDS-related NHL can also include certain types of intermediate and high-grade lymphomas, including Burkitt lymphoma.

The outcome for patients with AIDS-related NHL depends on the type of lymphoma and on the person's immune function, as well as other factors. People with advanced NHL, a helper T-cell count less than 200, and/or who don't get anti-HIV drugs don't usually do as well as people without these factors.

The best treatment for AIDS-related NHL is much like the treatment of NHL in those without HIV infection. At one time, treatment was made up of low doses of chemotherapy. But while taking anti-HIV drugs, many patients can be treated with standard chemotherapy doses.

For more information on HIV/AIDS-associated NHL and its treatment, please see our document, Non-Hodgkin Lymphoma.

Pre-cancerous cervical changes and invasive cervical cancer

HIV-infected women are at high risk for getting cervical intraepithelial neoplasia (CIN). CIN is the growth of abnormal, pre-cancerous cells in the cervix, the lower part of the uterus (womb). Over time, CIN can progress to invasive cervical cancer, in which the cancer cells grow into deeper layers of the cervix.

CIN must be treated to keep it from invading. This is done by removing or destroying the outer layers of cervical cells. Studies have shown that untreated CIN is more likely to progress to invasive cervical cancer in HIV-infected women than in women who don't have HIV. The standard treatments for CIN do not work as well in HIV-infected women as they do in women without HIV. The chance of the disease coming back after treatment is high, especially in women with T helper cell counts less than 50.

HIV-infected women with invasive cervical cancer and good immune function tend to do well with surgery and the same treatments that women without HIV get. Those who have more advanced disease respond poorly to radiation therapy alone. Chemotherapy has been used in women with advanced or recurrent disease, though the women must be watched closely after treatment to be sure the cancer doesn't come back. During cancer treatment, the woman's immune status must be watched and her HIV infection treated. Anti-HIV drugs are usually given to improve the treatment outcome for HIV-infected women with invasive cervical cancer, no matter what her T helper cell counts are.

Women with cervical cancer tend to fare better if they do not have AIDS, and those with T helper cell counts higher than 500 have better outcomes. For more detailed information on cervical cancer and its treatment, please see our document, Cervical Cancer.

Non-AIDS-related cancers

With more widespread use of anti-HIV drug treatment, AIDS-related cancers are being seen less often. But as people with HIV are living longer, they are developing cancers that are not clearly linked to HIV, such as lung, throat, liver, intestinal, and anal cancers as well as Hodgkin disease and multiple myeloma. Most of the time, treatment includes anti-HIV drugs along with standard cancer treatments. At the same time, any other needed treatments for HIV (such as antibiotics to prevent infections) are used.

Some of the cancers that are found more often in people with HIV are related to other risk factors, such as smoking. In one study, for instance, more lung, lip, mouth, and throat cancer were found in people with HIV, but mainly in those who smoked. Some of these types of cancer can be prevented by avoiding cancer risk factors.

Other HIV-related cancers are linked to common viruses already present in the body. They can cause cancer in people with and without HIV, but the risk may be higher in people with HIV because their immune systems are less able to control the viral growth. For example, human papillomavirus can cause penile, vaginal, vulvar, anal, tongue, and tonsil cancers as well as cervical cancer. For more on this, see our document, Human Papillomavirus (HPV), Cancer, and HPV Vaccines -- Frequently Asked Questions.

If cancer is found, treatment is based on cancer type and stage. In general, people with HIV and cancer are treated much like those without HIV infection. Cancer treatment may sometimes have to be changed because of other conditions in people with HIV infection. But even with standard treatment, people with HIV may still have slightly lower success rates with certain types of cancer, depending on the state of their immune systems and other factors. Because of this, doctors are studying various cancer treatments and their outcomes in people HIV infection.

Studies are also underway to look at whether there are special screening tests for cancer that may be helpful to HIV-infected patients. Already, women with HIV have special cervical cancer detection guidelines because they are at higher risk for invasive cervical cancer. (See section "Preventing, detecting, curing, and controlling opportunistic conditions" in "How are HIV and AIDS treated?") Because people with HIV are also at high risk of anal cancer, for instance, a screening test very much like the Pap smear is being looked at to find out if it is a good way to find anal cancer in its early stages. If the test improves survival or other outcomes, it may later become a standard cancer screening test for people with HIV infection.

In the meantime, the cancer detection tests that are recommended for people without HIV can also help detect cancer in those with HIV. And, your doctor and dentist may take extra care with doing cancer-related checkups to keep a close watch for early signs of cancer. If you are interested in more cancer screening options, ask your doctor about clinical trials for cancer detection in people with HIV (see "Clinical trials" below).

For more information on any type of cancer and its treatment, please visit our web site at www.cancer.org or call us at 1-800-227-2345.

Clinical trials

Clinical trials are carefully controlled research studies that are done with volunteers. Clinical trials are used get a closer look at promising new treatments or procedures. They are only done when there is some reason to believe that the new treatment being studied may be better than the best standard treatment.

You may have heard about clinical trials being done for people with HIV or for people with HIV and cancer. Or maybe someone on your health care team has mentioned a clinical trial to you.

If you would like to take part in a clinical trial, start by asking your doctor if your clinic or hospital conducts clinical trials. There are requirements you must meet to take part in any clinical trial. If you do qualify for a clinical trial, it is up to you whether or not to enter (enroll in) it.

Clinical trials are one way to get state-of-the art treatment. They are the only way for doctors to learn better methods to treat HIV, cancer, and other serious illnesses. Still, they are not right for everyone.

If you are looking for information on HIV or AIDS-related clinical trials, you can visit www.aidsinfo.nih.gov any time. Or you can call 1-800-448-0440 between noon and 5 p.m. Eastern time, Monday through Friday.

You can get a lot more information on clinical trials in our document called Clinical Trials: What You Need to Know. You can read it on our Web site or call our toll-free number (1-800-227-2345) and have it sent to you.

More cancer treatment information

For more details on cancer treatment options – including some that are not addressed in this document – the National Cancer Institute (NCI) is a good source of information.

The NCI provides cancer treatment guidelines via its telephone information center (1-800-4-CANCER) and its Web site (www.cancer.gov). Detailed guidelines intended for use by cancer care professionals are also available on www.cancer.gov.