Older HIV-positive men do not have an increased risk of abnormal prostate antigen test

Older HIV-positive men do not appear to have an increased risk of having elevated levels of prostate specific antigen (PSA), a key test used to diagnose men at risk of prostate cancer, according to a study published in the October edition of HIV Medicine. In a cohort of older HIV-infected and at-risk men investigators found that the only factor significantly associated with elevated PSA was older age. HIV infection did not increase the risk of elevated PSA. The investigators suggest that PSA tests can be used without modification in their criteria for abnormality, to screen HIV-positive men for prostate problems.

Potent anti-HIV therapy has led to a dramatic reduction in the incidence of the AIDS-defining cancers Kaposi’s sarcoma and non-Hodgkins lymphoma in HIV-positive patients. But some cancers, such as anal cancer caused by infection with high-risk strains of human papilloma virus, still occur more frequently in HIV-positive individuals.

Prostate cancer is usually considered a disease of older men. But there is also some evidence suggesting that men with a history of immune suppression may have an increased risk of the condition. It is known that men who have received immunosuppressive therapy after organ transplants have an increased risk of prostate cancer.

Thanks to potent anti-HIV therapy, many men with long-term HIV infection are now surviving into older age, and prostate cancer may therefore become a health concern. There are conflicting data regarding the incidence of the cancer in older HIV-positive men .

Investigators from the CHAMPS study (Cohort of HIV at-risk Ageing Men’s Prospective Study) in New York, which is exploring the effects of ageing, including atherosclerosis and bone loss in men aged 49 and over with or at risk of HIV, wished to see if HIV-positive men had an increased risk of elevated PSA levels. Since 1986, blood tests have been used to measure PSA levels to screen men for the risk of prostate cancer, and men with PSA levels above 4.0ng/ml are considered to have elevated PSA levels and are recommended to have a digital prostate examination and to be referred for expert urological evaluation.

A total of 534 men were included in the study, of these 224 (42%) were HIV-positive and the median age was 53 years. Three-quarters of the men reported being sexually active, 27% said that they had sex with other men, two-thirds smoked cigarettes, and 16% said that they had used steroids or testosterone. Prostate cancer had previously been diagnosed in six men.

Of the HIV-positive men, half had a CD4 cell count between 200 – 500 cells/mm³, 31% had a CD4 cell count above 500 cells/mm³ and 19% had a count below 200 cells/mm³. HIV-positive men were on average a year younger than HIV-negative men, and were more likely to have had a previous diagnosis of cancer (8% versus 3%, p = 0.04).

In all, 20 men (4%) had PSA levels above 4ng/ml. The only factor significantly associated with increased PSA was older age (p < 0.001), with the risk increased six-fold for men over 61. The proportion of HIV-positive and HIV-negative men with elevated PSA did not differ significantly (3% versus 5%).

Although all 20 men with elevated PSA levels were referred for urological evaluation, only nine of these men attended. One HIV-positive man and one HIV-negative man had prostate cancer confirmed after biopsy.

“In the present study, among older men with or at risk for HIV infection, only 4% had elevated PSA levels, with no significant difference by HIV status”, write the investigators, adding, “older age was the only factor associated with elevated PSA level.”

They conclude that PSA tests, using normal thresholds, can be used to screen HIV-positive men for prostate abnormalities.