December 19, 2012
Cancer is the uncontrolled growth of abnormal cells in the body. Cancer cells are called malignant cells. Malignant means bad and getting worse.Cancer is the uncontrolled growth of abnormal cells in the body. Cancer cells are called malignant cells. Malignant means bad and getting worse.
Cancer has been associated with AIDS from the beginning of the epidemic. A group of unusual cases of Kaposi's sarcoma (KS) -- which normally shows up in older men -- was identified in young men in Los Angeles. See fact sheet 511 for more information on KS.
Many types of cancer occur in people with HIV. Some cancers, called AIDS-defining cancers, are part of the official definition of AIDS. They include KS, Non-Hodgkin's Lymphoma (see fact sheet 512), and severe cervical cancer.
The official Centers for Disease Control definition of AIDS includes people who test positive for HIV and who have one of the following cancers: invasive cervical cancer (see fact sheet 510), non-Hodgkin lymphoma, or KS.
With the use of antiretroviral therapy, the rates of these AIDS-related cancers have dropped significantly. At the same time, people with HIV are at higher than average risk for several other cancers, including Hodgkin lymphoma and cancers of the anus, lung, liver, and skin, The number of cases of these other cancers is increasing in people with HIV.
Several studies found higher rates of some cancers in people with HIV, compared to the general population. Many factors could explain this: People with HIV are living longer. Older age is linked to higher rates of cancer.
People with HIV have a high rate of smoking, which contributes to several types of cancer. HIV infection weakens the immune system. This might allow some cancer cells to multiply. HIV also causes ongoing activation of the Immune system. This may increase some cancers. Some cancers (such as KS and non-Hodgkin's lymphoma) appear to be linked to the lowest (nadir) CD4 count a person had. Several cancers are linked to viral infections. These are shown in the following table.
|Kaposi's Sarcoma (see fact sheet 508)||Human herpes virus 8|
|Non-Hodgkin's Lymphoma (fact sheet 512)||Human herpes virus 8, Epstein-Barr virus|
|Cervical and anal cancers (fact sheet 510)||Human papilloma virus (HPV)|
|Hodgkin's Disease||Epstein-Barr Virus|
|Skin cancers (some)||Human papilloma virus|
|Liver cancer||Hepatitis B, Hepatitis C|
People with HIV have higher rates of these infections than the general population.
Some cancers appear in people with HIV at a younger age than in the general population. Some people think that HIV accelerates aging, and that cancers are one sign of this..A careful study suggested that this is not true for most cancers. The study found that most people with HIV are studied at younger ages than the general population. Most people with HIV are between ages 30 and 55, so cancers seem to occur at younger ages. For the general population, increasing age is linked to higher rates of cancer. As the AIDS population ages, the age of cancer cases will increase.
However, people with HIV do appear to develop anal cancer, lung cancer, and Hodgkin lymphoma at a younger age. This may be due to the effects of HIV on these cancers. It could also be caused by early exposure to risk factors for these types of cancer, such as earlier age of starting smoking or sexual activity (leading to HPV infection). Also, people with HIV are monitored more carefully from a younger age, so cancers may be detected earlier.