A recent study published in the Journal of Acquired Immune Deficiency Syndromes (JAIDS) found that the incidence of non-AIDS defining malignancies, such as anal and lung cancer, is increased for HIV infected individuals.

“Non-AIDS defining illnesses” includes all forms of cancers except skin, lymphoma, cervical carcinoma, Kaposi’s sarcoma and some ill-defined cancers. These are considered AIDS defining and are known to be of higher prevalence in HIV-positive individuals.

In this study, it was found that HIV-infected patients also have a higher risk of developing certain non-AIDS defining illnesses.

The study was conducted on 33,420 HIV-infected and 66,840 HIV-uninfected patients for a period between 1997 and 2004. The incidence rate of cancerous malignancies was measured. Factors such as age, gender, and race were taken into account.

The results showed that HIV-infected individuals were 60 percent more likely to have anal, lung, Hodgkin’s lymphoma, melanoma, prostate, and liver cancer than non HIV-infected individuals.

Roger Bedimo, Assistant Professor of Medicine at University of Texas Southwestern Medical Center and lead researcher of the study, explains the risks:

“Many of these cancers, like lung and liver cancer, despite being respectively two and three times more common among HIV patients than in non-HIV patients, are not associated with a lower CD4 count. So, even HIV patients with presumably good immune function are at much greater risk of cancers than non-HIV patients.”

One theory for the possible cause of this trend is that antiretroviral therapy that HIV-positive individuals undergo might increase their risk of developing those particular cancers.

Another possibility is that HIV-infected individuals are more prone to traditional cancer risk factors such as viral coinfections and lifestyle choices such as smoking.

Another theory is that HIV itself increases an individual’s chance of developing cancer inherently.

One weakness of the study is the lack of female participants; males represented about 98 percent of the study’s population.

Bedimo explains that the implications of the study “further investigate whether the implementation of screening measures, such as anal Pap smears, could lead to earlier detection of these cancers and better outcomes.”

This study has led to plans for future research “to further evaluate the impact of viral infections on the incidence of these cancers,” Bedimo states.

For more information, please see the original study in JAIDS (abstract) and the press release from Southwestern Medical Center.