Prostate test 'of little value' - The PSA test can reveal the
presence of cancer
A screening test which can reveal prostate cancer is too unreliable
to be recommended to patients, it is claimed.
PSA, or prostate specific antigen testing, is often offered
to older men as part of private health assessments.
However, a UK expert writing in the British Medical Journal
says it should not be widely used as it is not clear whether
it actually benefits patients.
Men testing positive do not fare better than those whose cancer
is only spotted when symptoms emerge, it is claimed.
The prostate gland is found in men near the bladder, and makes
an ingredient of semen.
Prostate cancer is the most common in men, and often, by the
time symptoms arise in aggressive cases, it has spread beyond
the gland itself.
This makes it far harder to treat successfully.
Cancer hint
The PSA blood test looks for a protein produced by prostate
cells - higher levels suggest either a benign prostate enlargement,
or perhaps the presence of a cancer.
However, it does not confirm cancer - a man needs to have a
biopsy operation to make sure - and the test is often wrong.
At present the one certainty about PSA testing is that it causes
harm
Professor Malcolm Law, Wolfson Institute of Preventive Medicine
Another problem is that prostate cancer is often a relatively
slow-growing disease of older men - who, if left untreated,
would die with the disease rather than of it.
A positive PSA test can mean that many cancers which could easily
have been left untreated with no ill effects for the man are
removed by surgeons, creating unnecessary risk - and a chance
of disabling side-effects such as incontinence and loss of sexual
function.
'Unproven value'
Many experts in the UK are unconvinced that the PSA test is
worth giving to apparently healthy men.
However, some firms routinely offer the test to men over 50
years old.
Professor Malcolm Law, from the Wolfson Institute of Preventive
Medicine in London, wrote in the BMJ that public health authorities
should not advocate tests of "unproven value".
He said: "At present the one certainty about PSA testing
is that it causes harm.
"Some men will receive treatment that is unnecessary -
and the treatment will cause incontinence, impotence and other
complications.
"In one study over two-thirds of men receiving either radical
prostatectomy (surgical prostate removal) or radiotherapy were
affected."
Breast advice
He is also critical of breast and testicle self-examination
advice - suggesting that this advice also leads to unnecessary
treatments.
Self-examination advice has now been dropped in favour of breast
and testicle "awareness", in which people are urged
to be alert for changes, rather than actively seek them out.
Dr Chris Hiley, Head of Policy and Research at The Prostate
Cancer Charity, agreed that PSA screening was not worthy of
recommendation by doctors.
She said: "We're not in favour of PSA screening.
"We can measure the harm caused by prostate testing - unfortunately
we can't measure the benefits.
"Men considering taking a test like this should think very
hard and get good advice about whether it is suitable."
zur Originalquelle (British Medical Journal)
