PSA was never licensed to detect cancer.  It was approved ONLY to follow
the results after prostate cancer had been treated.  PSA was quickly used
for what it had never been tested for.  Now 20 years later real research has
shown it to be simply a mystery tool which causes men to get a biopsy and of
course since we will all have prostate cancer if we live to be 80, at some
point everyone who undergoes a biopsy will be diagnosed.

But here is the key quote:

"The fact that many prostate cancers, including high grade tumours, are
missed at low PSA concentrations could explain the discrepancy between the
high rate of PSA screening over the past 15 years and the lack of reduction
in prostate cancer mortality in the United States, Professor Thompson said."

In short, PSA is a failure as a screening tool.

An interesting article, but nothing much new in it.  Other studies have
shown similar results,  particularly those of Catalona, et. al.   Other
criteria, such as PSA velocity, i.e., the rate of increase of PSA, may
be helpful, and some think that the free PSA percentage may be of use.
But everyone agrees that PSA screening, followed by biopsy is an
uncertain tool.   It leads to a significant number of  unnecessary
biopsies and it misses some cancers.   In addition, some of the cancers
discovered this way need not be treated.   There are some estimates of
how many such cancers there are, but nothing really definitive is known.
  Unfortunately, right now we don't have much else to go on.

One thing I don't understand.   The article mentions the lack of
improvement in prostate cancer mortality in the US in the past 15 years.
  In fact, the absolute number of deaths due to prostate cancer has
decreased during this period despite the fact that the vulnerable
population has been increasing.   This has not happened in other
countries such as Sweden which don't encourage PSA screening.  That by
itself is not proof certain that PSA screening is effective, but it
doesn't seem that the data support the opposite conclusion as the
article suggests.

I've now looked at the  paper.   The study purports to show that there
is no clear cutoff point for distinguishing which men should have
biopsies and which shouldn't.   Its results are consistent with the
results of others such as Catalona, although I was puzzled that these
results were not quoted in the bibliography.  Of course, no one or two
studies can establish such a matter definitively, but the results do
seem convincing.

It should be noted that the study says nothing whatsoever about the
effectiveness of PSA testing as employed today in reducing cancer
mortality.  Various other statements of a general nature are made in the
introduction, and the authors or others may try to draw conclusions
about such matters from this study, but the study itself was not
directed to that end.   One has to be careful to separate statements in
a scientific paper which are conjectural in nature from that which the
study actually addresses.

Fact: Prostate cancer mortality has declined in the US, as well as in
other geographies (Tyrol, Orebro studies), were routine PSA testing has
been implemented.  The following article is yet another one making this
observation...Ron

Early PSA screening may reduce risk of prostate cancer death: study
SHERYL UBELACKER
Fri Jul 8,12:38 AM ET

TORONTO (CP) - Early screening for prostate cancer in men without
symptoms could significantly reduce their risk of going on to develop
an advanced and usually deadly form of the disease, a Canadian study
suggests.

Researchers at the universities of Toronto and British Columbia found
that early PSA testing may reduce the risk of metastatic prostate
cancer - the kind that spreads beyond the walnut-sized gland - by more
than a third.

The study compared the PSA testing histories of 236 men with advanced
prostate cancer against those of a control group of men without
metastatic cancer - 462 who either didn't have the disease at all or
had a localized tumour.

"What we found was, in fact, that the risk of metastatic prostate
cancer was about 35 per cent less in the men who had been screened,"
said study co-author Dr. Vivek Goel, a professor of health policy
management and evaluation at the University of Toronto.

The screening tool is a simple blood test that detects levels of what's
known as prostate specific antigen, or PSA. While small amounts in the
blood are normal, higher levels could indicate cancer.

Yet the test remains controversial because it is not foolproof and may
cause undue distress. High PSA levels can exist when no cancer is
present or a tumour may be a type that doesn't spread to other parts of
the body, so men can live normal lives for many years to come.

But PSA testing may also flag the type of prostate cancer that will go
on to spread if left untreated, said the researchers.

"Our study . . . adds to the body of evidence that shows that it does
have potential for having a fairly significant effect in reducing the
risk of advanced prostate cancer and, by extrapolation, the death from
prostate cancer," Goel said.

That's because detecting prostate cancer before it has spread allows
for early and effective treatment.

The study adds weight to the argument that PSA testing should be
routine for men - as mammography and pap smears are for women - not
just when a doctor suspects cancer because of symptoms, he said. "There
may be greater benefit from an organized screening program."

But the test, when used strictly as a screening tool, is covered by
only about half of Canada's provincial health plans.

An estimated 20,500 Canadian men will be diagnosed with prostate cancer
this year, and about 4,300 will die. Prostate cancer is the
second-highest cause of cancer death among North American men after
lung cancer.

"Our study shows a fairly significant benefit for early screening using
the prostate specific antigen test, so these results are important for
men and their doctors," said Dr. Jacek Kopec, professor of health care
and epidemiology at the University of British Columbia and lead author
of the paper.

The head of the Canadian Cancer Society, which helped fund the study,
called the findings welcome news for Canadian men.

"The results of this study are interesting and add to the body of
evidence about the PSA test," said Dr. Barbara Whylie.

"We look forward to the results of two other large, ongoing trials to
validate these findings," Whylie said in a statement. "In the meantime,
we will continue to encourage men to discuss this test with their
doctors until more definitive answers about the benefits of the PSA
test are available."

The study, published in the August issue of the Journal of Urology,
recruited men from the Greater Toronto Area in 1999-2002. They ranged
in age from 45 to 84; the average age of prostate cancer diagnosis was
68.

Researchers obtained self-reported information about their lifestyles,
health history and use of health services. They also received
permission to review medical records and history of PSA screening.