New Guidelines for Prostate Cancer Screening
American Cancer Society Says Men Need to Weigh Benefits and Limits of PSA Tests
March. 4, 2010 -- The American Cancer Society says men should talk to their
doctors about the benefits and limitations of prostate
cancer screening before deciding whether to be tested.
The group's newly revised guidelines make it clear that prostate specific antigen (PSA) blood testing should
not occur unless this discussion happens.
The American Cancer Society stopped recommending routine PSA screening more
than a decade ago, but the new recommendations are unequivocal in calling for
all patients to be informed about the benefits and risks of PSA testing before
screening takes place.
"There is a lot of uncertainty with prostate cancer screening," American
Cancer Society Director for Prostate and Colorectal Cancers Durado Brooks, MD,
MPH, tells WebMD. "Right now it is not entirely clear that finding a man's
prostate cancer early will save his life."
Two studies reported early last year heightened long-standing concerns that
the risks of routine prostate cancer screening may outweigh the benefits.
Benefits and Limits of PSA Tests
A large trial supported by the National Cancer Institute failed to show a
reduction in prostate cancer deaths associated with PSA screening over an
average of seven years of follow-up.
Another study from Europe found that routine screening reduced the rate of
prostate cancer death by 20%.
But researchers also estimated that 1,400 men would have to be screened and
close to 50 men whose cancers were detected through screening would have to be
treated to prevent a single cancer death.
Fred Hutchinson Cancer Center biostatistician Ruth Etzioni, PhD, who
co-wrote the revised American Cancer Society guidelines, says it isn't that
"The risk-benefit ratio for screening is very different for a man in his 50s
and a man in his 70s," she says.
According to Etzioni's own research, one in four men whose prostate cancer
is detected through PSA screening actually has clinically irrelevant,
slow-growing cancer that would never cause symptoms.
And one in four men will die of their cancer, she says.
Before routine screening, she says about 9% of men received a diagnosis of
prostate cancer during their lifetimes and about 3% of men died of the
In the screening era, about 18% of men are now diagnosed with prostate
cancer and 2% to 2.5% die as a result.
"The death rate has definitely come down, but treatments are now better and
other changes have occurred so it is unlikely that this is completely related
to screening," Etzioni says.
The risk of being diagnosed with a clinically irrelevant prostate cancer is
much greater for older men than for younger ones, she adds.
Impotence, incontinence, and bowel issues
are common side effects of prostate
The PSA Screening Conversation
Brooks says the conversation between a man and his health care provider
should focus on his individual risk.