Well that's interesting. It certainly sheds some light on the anal cancer study I've been involved in. In fact anal cancer is specifically mentioned as one of the cancers that can be caused by HIV.
The US Dept of Health and Human Services has released a new list of known carcinogens this month with some new additions. One of them being the HIV virus.
What evidence is there that HIV causes cancer?
There is sufficient human evidence to show that HIV increases the risk of seven types of cancer that are caused by infections from other viruses — Kaposi sarcoma; non-Hodgkin lymphoma; Hodgkin lymphoma; cervical, anal, vaginal/ vulvar, and penile cancers; and two other types of cancer – conjunctival eye cancer and non-melanoma skin cancer. Numerous studies in different populations provide evidence that people with HIV infection have a higher risk for these cancers compared to uninfected people of the same age.
Studies evaluating markers of a body’s weakened immune system, or immunosuppression, such as decreased CD4 T cells, also support the link between these human viruses and cancer. Three of these cancers — Kaposi sarcoma, non- Hodgkin lymphoma, and cervical cancer — are considered AIDS-defining cancers. A diagnosis of any of these three cancers means the HIV infection has progressed to AIDS.
There is only limited evidence from studies in humans for an association between HIV and lung cancer, liver cancer, or oral-related cancers, such as those occurring in the mouth or throat.
HIV-1 infection is associated with over 3,900 excess cancers in the United States. Fortunately, treatments referred to as HAART, highly active antiretroviral therapy, or cART, combination antiretroviral therapy, have been shown to reduce the level of HIV-1 in the blood and substantially decreased the risk of Kaposi sarcoma and non-Hodgkin lymphoma. National Toxology Program (PDF)