NSAIDs May Mask Prostate Screenings, Or Lower Risk – Researchers

Regular use of nonsteroidal anti-inflammatory drugs may cause an under-diagnosis of prostate cancer, rather than reducing the risk of the condition as some research suggests.

A research team from the University of Rochester (N.Y.) Medical Center says the findings suggest regular NSAID or acetaminophen use by men may reduce serum prostate-specific antigen levels and lower prostate cancer risk.

Alternatively, NSAID use may reduce serum PSA levels "without truly affecting" the onset of prostate cancer, they note.

In a study published Sept. 8 in the journal Cancer, the authors examined 2001-2002 National Health and Nutrition Examination Study data on 1,319 men over the age of 40, their use of NSAIDs and acetaminophen and their PSA levels. NHANES was conducted by the Centers for Disease Control and Prevention.

According to the data, men who used NSAIDs or acetaminophen "nearly every day" had PSA levels -a blood biomarker measured during prostate screenings that physicians look at to determine if a man is at risk for cancer - 10 percent lower than men who did not.

"Whether this is indicative of a protective effect on prostate cancer risk or masks possible prostate injury resulting in reduced detection of prostate cancer is unclear," write Eric A. Singer, Ganesh S. Palapattu and Edwin van Wijngaarden.

Singer, a urologist at the Rochester center, said since PSA levels are indicators of cancer risk, if PSA "was lower, more men would be thought to be at lower risk of developing cancer and so fewer biopsies would be done. If you do fewer biopsies, you are going to find less prostate cancer."

"On the one hand it could be beneficial. On the other hand, it could be just changing what we see when we do the blood test," he said.

He and his colleagues are not recommending changes to prostate screening tests or men's NSAID use. "Right now, based on this study, it's far too early to recommend changes," he said.

Singer noted that NSAIDs and aspirin have "long been thought of as a really good candidate" for reducing prostate cancer risk.

Since one hypothesis for prostate cancer is that it might be caused by chronic inflammation, Singer says he and his team thought the drugs that reduce inflammation could decrease prostate inflammation as well, maybe even lowering PSA levels.

While the authors say their results are in line with other studies that found NSAIDs may reduce the risk of prostate cancer, they say the findings are preliminary and do not prove the link.

"This was a limited study focusing on PSA, and we cannot address the possible impact of these medications on the development of prostate cancer," Singer said.

Singer said the NHANES data do not cover enough time to establish a link between NSAID use and the likelihood of prostate problems. "We don't know what happened to these men five, 10, 15 years down the road," he said.

Information from the men over a longer period is needed to move this research forward, Singer said. Future studies should be "much larger and much longer," he added.

A future longitudinal study should address specifically whether frequent NSAID use decreases inflammation and risk, or "artificially lower[s] the number of cases that were found," he said.

Singer said the challenge in designing a study will be in determining what the decrease in PSA levels means.

Singer also stresses that his team's results point to the importance of physicians asking their patients about NSAID use and to be aware of all the medications they are taking.

- Katie Stevenson ([email protected])