Prostate Test: No Survival Benefit?
Men Who Died Had PSA Cancer Screening Test as Often as Those Who Lived
No Survival Advantage Seen
From approximately 72,000 veterans receiving care at 10 VA medical centers in New England, Concato and colleagues identified 501 men aged 50 and older who were diagnosed with prostate cancer between 1991 and 1995 and had died of the disease by 1999. An equal number of living VA patients, matched for age and place of treatment, were included in the study as a comparison group.
The researchers found that 14% of the men who died of prostate cancer and 13% of those who did not die had been screened using the PSA test. The overall risk for death after adjusting for race and coexisting medical conditions showed no increased risk.
"If screening worked, men who died would have had less testing than those who lived," says Concato.
The Yale University professor of medicine suggests that men with strong fears of prostate cancer and those who fully understand the potential risks associated with treatment may still want to have routine PSA testing.
Informed men who feel the potential risks outweigh the benefits should not be pressured into having the test, he says.
"Doctors should mention that the PSA test isn't perfect and that screening may lead to possible harm as well as potential benefit," he says. "The benefits include the potential for improved survival in some men. The harms include possible treatment-related side effects, including incontinence and impotence, for therapies that may be unnecessary (for slow growing tumors) or ineffective (for aggressive ones)."
In an editorial accompanying the study, Michael J. Barry, MD, of Massachusetts General Hospital, wrote that it remains to be seen if PSA testing results in improved prostate cancer survival.
Two large clinical trials under way in the United States and in Europe should provide more definitive answers, he says. The results of these studies should give more information about the effectiveness of prostate cancer screening. Results from the trials are expected sometime in 2009.
"I have been writing that we need to wait for trials to see if prostate cancer screening does more good than harm for so long, sometimes I despair of ever knowing the answer," he writes, adding that "help is now not that far away."