ROCHESTER, New York—Regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce serum levels of prostate specific antigen (PSA), potentially blunting the detection of prostate cancer suggests new research in the October 15, 2008 issue of Cancer.1 The implications of these data for a possibly protective effect against development of prostate cancer are unclear.

“Given the widespread consumption of NSAIDs and the regular use of PSA for the assessment of prostate cancer risk, the potential implications of the current study’s findings may be substantial and warrant further investigation.”—Eric A. Singer, MD, MA
“Given the widespread consumption of NSAIDs and the regular use of PSA for the assessment of prostate cancer risk, the potential implications of the current study’s findings may be substantial and warrant further investigation,” conclude researchers led by Eric A. Singer, MD, MA, a urologist at the University of Rochester Medical Center in New York.

Researchers measured PSA levels in 1319 men aged >40 who participated in the 2001-2002 National Health and Nutrition Examination Survey. Men who reported using NSAIDs or acetaminophen regularly had PSA levels ~10% lower than those who did not take these drugs (P = .038), although the difference in acetaminophen users was not statistically significant. The majority of PSA concentrations were <4 ng/mL.


In the study, 19.8% of men were “regular users” of NSAIDs. Regular use was defined as “nearly every day.” Moreover, 1.3% of the men were regular users of acetaminophen. These individuals had serum PSA concentrations that were 0.76 the level of men who did not take acetaminophen, however, this finding was not statistically significant.

Men who consumed both NSAIDs and acetaminophen had 80% higher PSA values than men who took neither of the drugs, but this was not statistically significant (P = .24).

“The findings of the current study suggest that regular NSAID consumption may reduce serum PSA levels. 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,” Dr. Singer wrote.

The inflammation supposition

Chronic inflammation is associated with several cancers. But “the causal nexus is not well established in prostate cancer,” the researchers wrote. “Inflammation is also believed to play a role in prostate carcinogenesis through multiple mechanisms such as infection, hormonal changes, physical trauma, urine reflux, and dietary habits.”

Translating research into practice

“Unfortunately, we don’t know whether regular NSAID use decreases prostate cancer risk or delays its detection,” said Durado Brooks, MD, director of prostate and colorectal cancers at the American Cancer Society in Atlanta.

“Men who took these medications regularly had slightly lower PSA levels, but these were not correlated with prostate health,” he told MSKreport.com. “For all we know, there could have been more cancers in the NSAID group than in those in men not taking these medications.”

The bottom line is that “we don’t know what this means with regard to prostate cancer. There is certainly a chance that men who have prostate cancer and are taking these medications may have a delay of diagnosis if the medications suppress PSA levels,” Dr, Brooks said. “The new information would be more valuable if there were pathological or historical correlations. It is just one more piece of information that says NSAIDs may have some impact on the prostate gland, but we have no idea what that impact is.”

A. Mark Fendrick, MD, a professor of internal medicine and of health management and policy at the University of Michigan in Ann Arbor agreed. “Since a causal relationship between NSAID use and PSA levels [or increased rates of prostate cancer] has not yet been established, this single descriptive study is not likely alter standard clinical practice. The modest reduction in PSA levels reported may move clinicians to be more diligent regarding follow-up PSA testing for those NSAID users whose PSA levels are in the ‘high-normal’ range.”

Reference

1. Singer EA, Palapattu GS, van Wijngaarden E. Prostate-specific antigen levels in relation to consumption of nonsteroidal anti-inflammatory drugs and acetaminophen. Results from the 2001-2002 national health and nutrition examination survey. Cancer. 2008;113:1-5.