October 8, 2009

Maintaining High CD4s Decreases Cancer Risk

People with CD4 counts above 500 have a lower risk of developing a range of the most common cancers, according to a study published October 8 in Lancet Oncology and reported by aidsmap. These data, the researchers suggest, lend weight to arguments that HIV treatment should be started earlier than current U.S. guidelines recommend.

Researchers have long known that certain AIDS-defining cancers, such as Kaposi’s sarcoma and non-Hodgkin’s lymphoma, are more likely to occur when CD4 cell counts are less than 200. More recently, however, a host of non-AIDS-related cancers—such as anal cancer and liver cancer—have become more common in people with HIV, frequently occurring at higher CD4 counts.

To determine the role that CD4 counts, viral load and antiretroviral (ARV) therapy play in the risk for developing seven of the most frequently diagnosed cancers in people with HIV, Marguerite Guiguet, PhD, from the Institut National de la Santé et de la Recherche Médicale (INSERM) in Paris, and her colleagues examined the medical records of 52,278 HIV-positive patients enrolled in the French Hospital Database on HIV infection (FHDH) ANRS CO4 cohort study.

The data were collected between 1998 and 2006. Kaposi’s sarcoma was the most frequently diagnosed cancer, followed by non-Hodgkin’s lymphoma and then lung cancer. Also explored were rates of anal cancer, cervical cancer, liver cancer and Hodgkin’s lymphoma.

With the exception of anal cancer, Guiguet’s team reported that a person’s current CD4 count was the most predictive factor in determining his or her risk for developing the most commonly diagnosed cancers. The researchers were not surprised to find that many of the cancers were most common in people with fewer than 200 CD4s—a typical finding in other studies conducted to date. Of notable interest was the increased risk in people with CD4 counts that were only moderately suppressed. According to the reported analysis, the risk for developing six cancers was significantly increased in people with CD4 counts between 350 and 499, compared with people who had a CD4 count above 500.

While current CD4 count was not highly predictive of an anal cancer diagnosis, a person’s risk for anal cancer did increase by 30 percent for every year he or she spent with a CD4 count less than 200.

These findings, Guiguet and her colleagues suggest, lend further weight to ongoing arguments that HIV treatment should be started even earlier than current U.S. guidelines recommend—when the CD4 count falls below 350. “Our results suggest that combination antiretroviral therapy would be most beneficial if it restores or maintains the CD4 cell count above [500], thereby indicating earlier diagnosis of HIV infection and earlier treatment initiation.”

NEW! Scroll down to comment on this story.

Previous Comments: