New Debate on Prostate Cancer Screening
U.S. Study Shows PSA Test Doesn't Save Lives; European Study Shows Modest Benefit
March 18, 2009 -- Interim findings from an eagerly awaited ongoing
government study show no evidence of a survival benefit associated with
aggressive screening for prostate cancer using the prostate specific antigen
More prostate cancers were detected over an average of seven years of
follow-up among men who had regular PSA testing in addition to digital rectal
exams compared to usual care, which could have included screening. But the
increase in prostate cancers did not translate into fewer deaths from the
The findings are certain to add to the controversy surrounding the value of
PSA testing for prostate cancer screening, and the debate about whether current
screening practices have led to overdiagnosis and overtreatment of prostate
The study, funded by the National Cancer Institute was published online
ahead of publication in the March 26 issue of the New England Journal of
"What this report tells us is that there may be some men who are
diagnosed with prostate cancer and have the side effects of treatment, such as
impotence and incontinence, with little chance of benefit," NCI director
John E. Niederhuber, MD, says in a news release.
"Clearly, we need a better way of detecting prostate cancer at its
earliest stages and as importantly, [we need] a method of determining which
tumors will progress."
Screening Beneficial in European Study
To add to the confusion, findings from a major European trial appearing in
the same issue of the New England Journal of Medicine did show a modest,
20% survival benefit associated with PSA screening in men followed for an
average of nine years.
Both the U.S. and the European studies will be presented this week at the
European Association of Urology annual meeting in Stockholm, Sweden.
For every 10,000 men screened with PSA over a nine-year period in the
European trial, seven fewer deaths from prostate cancer were reported.
But the European researchers estimated that 48 additional men whose cancers
were detected as a result of screening would need to be treated to avoid one
prostate cancer death.
That compares with about 10 additional treatments among women screened with
mammography needed to prevent one death from breast cancer, prostate cancer
screening researcher Michael J. Barry, MD, of Harvard Medical School tells
Barry, who wrote an editorial that appeared with the studies, adds that the
new research helps to quantify the benefits and risks associated with PSA
"When you look at the two trials together it becomes clear that the
benefits, in terms of survival, are fairly modest," he says. "They are
similar to what we see with mammography, but in my opinion it comes at a much
higher price in terms of overdiagnosis and overtreatment."