Mixed messages from prostate cancer screening studies
23 March 2009
New data evaluating the impact of screening on mortality provides
mixed messages on the value of prostate cancer screening. The US
Prostate Conditions Education Council (PCEC), a national organization
committed to men's health and a leader in prostate cancer screening,
announced that screening practices should be continued, based on new
data from two studies, including the preliminary data from the prostate
component of the Prostate, Lung, Colorectal, and Ovarian (PLCO) study in
Two studies featured in the 26 March 2009 issue of the New
England Journal of Medicine present findings from the PLCO study
and the European Randomized Study of Screening for Prostate Cancer
(ERSPC) (see MTB Europe story: Prostate cancer
screening could cut deaths by 20%).
Early data reported from the PLCO study found there was no early
mortality benefit from annual prostate cancer screening. Alternatively,
long-term data from the ERSPC study show that screening reduced the rate
of mortality by 20%. While the study designs differ, together they offer
an opportunity for comparison.
"More time and further investigation is needed to fully understand
and evaluate the impact of prostate cancer screening on mortality before
discontinuing screening practices," said Dr David Crawford, one of the
principal investigators of the prostate component of the PLCO study and
head of the Urologic Oncology Department at the University of Colorado
Health Sciences Center. Dr Crawford is also the founder and chairman of
"Since the Prostate-Specific Antigen test was made available, we have
seen a decrease in deaths attributed to prostate cancer. At this point,
it is inappropriate to summarily deny screenings for patients based on
these data," said Wendy Poage, president of the PCEC.
While the cancer community continues to seek long-term results, there
is already a wealth of research that shows the Prostate-Specific Antigen
(PSA) test as a valuable tool to assist in the diagnosis of prostate
cancer, as well as an enlarged prostate.
These studies show evidence that screening is associated with a fall
in mortality. While not perfect, the PSA test is the best screening tool
available right now. That is why the PCEC actively participates in
research to help advance PSAs, the development of new biomarkers and
"The truth is too many men, nearly 30,000, are dying from this
disease, which is survivable when discovered early," said Poage. "We
know for a fact that some men will be diagnosed with aggressive prostate
cancer that will eventually take their life. If caught early, through
screening, these lives could be saved. Discouraging or withholding
screening without firm evidence could cost men their lives."
The PCEC encourages men to 'Choose to Know — and Know to Choose'.
This means they should choose to know their PSA values, just as they
would their cholesterol, and know that there are many choices and
variables in determining if they need a biopsy and subsequent treatment
if cancer is found.
The organization recommends a baseline prostate health assessment,
including PSA and digital rectal exam (DRE), for all men at 40 years of
age and at 35 for men at high risk (including those with a family
history of prostate cancer and African-American men).
Based on this assessment, men with a PSA less than 1ng/ml should
begin annual screening starting at age 50. Those who have a PSA greater
than 1ng/ml should discuss additional testing and screening with their
doctor. The PCEC recommends annual screenings for these men. However,
the PCEC does not advocate for screenings if a man's life expectancy is
less than 10 years.
"For all we know, additional data from the trial may show a mortality
benefit with screening. As prostate cancer, in general, is a slow
growing disease, in the future the data may conclude that there is a
benefit to prostate cancer screening," continued Poage.
Both studies are ongoing with further updates anticipated. The PCEC
applauds the investigators of both trials for their contributions.