Cancers

Cancer is a group of diseases caused by cells that multiply out of control. People with HIV or AIDS have a higher risk of certain cancers than do people with healthy immune systems. In developed countries, four out of 10 people who have AIDS develop a cancer.

Some cancers are called AIDS-defining conditions. This means the cancer is due to having a weakened immune system. It is a sign that a person with HIV may be developing AIDS. AIDS-defining cancers are Kaposi’s sarcoma, cervical cancer and non-Hodgkin’s lymphoma.

People with HIV are also at a greater risk of developing cancers such as Hodgkin’s disease, multiple myeloma (a form of leukemia) or cancers of the anus, brain, blood vessels, eye, liver, mouth, throat, lungs, testicles, connective tissues (leiomyosarcoma) or skin.

These cancers are not regarded as AIDS defining. Their appearance isn’t related to a weak immune system. They may show up more often in people with HIV because of some other factor such as high-risk behaviors or sexual activity.

Symptoms

Having both HIV and cancer doesn’t change the signs of cancer. These vary depending on the type of the cancer and the part of the body it affects. More information on Kaposi’s sarcoma, cervical cancer, non-Hodgkin’s lymphoma and anal cancer is available in other sections of this website. Some cancers are more aggressive in people with HIV.

Causes

It is not yet known what the connection is between HIV and certain cancers. Having a weakened immune system is a factor. Many viruses that are otherwise harmless may lead to cancer in a person with HIV. These include:

• Human herpes virus 8 (HHV-8), which plays a role in developing Kaposi's sarcoma
• Human papillomavirus (HPV), which plays a role in developing anal and cervical cancers
• Epstein-Barr virus (EPV), which possibly plays a role in developing lymphoma
• Hepatitis B virus (HBV) and hepatitis C virus (HCV), which play roles in developing liver cancer

With the wider use of antiretroviral therapy, the number of cases of some cancers, like Kaposi’s sarcoma and brain lymphoma, has dropped. This could be because these cancers usually show up when CD4 cell counts fall. Antiretroviral therapy raises CD4 cell counts.  Even so, some studies show that some cancers like non-Hodgkin’s lymphoma are holding steady or even increasing. These cancers typically occur at higher CD4 cell counts.

Risk Factors

People with HIV who aren’t on antiretroviral therapy have a greater chance of developing AIDS-defining cancers than do other people. Smoking, heavy drinking, some foods and exposure to certain chemicals can all increase the risks of getting some kinds of cancer. For example, spending a lot of time in the sun without protection can increase the risk of getting skin cancer. 

Prevention

All people have some risk of getting cancer. Steps that can be taken to lower the risks include:

• Seeing a doctor for regular check-ups, blood tests and screening for early detection of cancer. These include tests such as a Pap test, which can screen for cervical cancer.
• Self-exams of the breasts or testicles to look for unusual lumps
• Being aware of any unusual bumps, sores or changes in how the body works, such as changes in bowel habits. These should not be ignored. They may require a doctor’s attention.
• Seeing a doctor about symptoms such as unexplained fever or weight loss.
• Eating a balanced diet rich in vitamins, nutrients and fiber.
• Regular exercise.  This along with a good diet can help the immune system fight viruses that may cause cancer.
• Not smoking.  Smoking raises the risks of lung cancer.
• Limiting alcohol use. Drinking too much alcohol puts a strain on the body. It also raises the risks of getting certain types of cancer such as mouth or throat cancer.
• Avoiding recreational drugs. As with smoking and alcohol, using recreational drugs can put a strain on the body and the immune system. In particular, drugs put stress on the liver, which is the organ that processes drugs and other chemicals in the body. Drugs that are injected increase the risk of getting cancer-causing viruses.

Diagnosis

Some cancers can be diagnosed on the basis of the symptoms and a physical examination. Often X-rays or other types of scans are needed to check for tumors.  Sometimes a sample of tissue is taken to check under a microscope.  This is called a biopsy.  How the diagnosis is done depends on the symptoms and what type of cancer is suspected.

Treatment

How cancer is treated depends on the type of cancer and how far advanced it is. Having AIDS makes treatment more difficult.  Some treatments used for treating cancer can weaken the immune system even more. Treatment for cancer should be done by a doctor who specializes in cancer (an oncologist).

Being on highly active antiretroviral therapy can help fight cancer. It is helpful if the doctor treating cancer also has experience with HIV.
Common treatments for cancer and issues for a person with HIV to be concerned about include:

• Chemotherapy. This uses chemicals that are either injected or taken as pills to kill cancer cells. Many of these chemicals focus on specific types of cancer. Studies have shown that antiretroviral therapy can improve a person’s response to chemotherapy. This helps people with AIDS-related lymphoma live longer.
• Radiation.  This uses high-energy beams, such as X-rays, to kill the cancer cells.
• Surgery.  This removes tumors from the body.  It is often used with chemotherapy and radiation therapy.
• Drugs.  Sometimes drugs can help keep cancer in check.  An example is tamoxifen, which is used to treat breast cancer.