Download Prostate-specific Antigen (PSA) testing

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Prostate-specific
Antigen (PSA) testing
Prostate-specific antigen (PSA) testing
What is prostate cancer?
There are many issues surrounding the PSA test –
especially around whether men should routinely
have the blood test.
Each year, around 25,000 men in the UK receive a
diagnosis of prostate cancer. Prostate cancer kills
about 10,000 men a year. The average age at
diagnosis is 75. It is rare in men under 50. It is
generally a slow growing disease.
Many people believe a PSA blood test finds out if a
person has prostate cancer.
This fact sheet disperses that myth and may help
you to understand why a test should not be taken
without the patient being fully informed. It explains
the implications of results and on a broader scale,
why PSA tests are not recommended as a
screening tool for prostate cancer.
We are not saying you should not have a PSA test,
but that we prefer you to know everything there is
to know before we take it.
What is BHP?
You will have been invited to attend the prostate
assessment clinic for investigations into your
urinary symptoms. Four out of every five men aged
over 50 years will have some degree of
enlargement of the prostate gland. Usually this
enlargement is caused by a non-cancerous
condition called Benign Prostatic Hypertrophy or
BPH.
The symptoms BPH can cause include increased
frequency of passing urine, a sudden urge to pass
urine, difficult in urinating or a weak flow of urine.
Is it treatable?
Treatment of BHP involves taking drugs or having
an operation often known as a “rebore”. Its actual
name is Trans Urethral Resection of Prostate or
TURP.
While BPH is by far the commonest cause of
problems with the prostate gland, it does not lead
to cancer, nor increase the risk of cancer
developing.
However, some of the symptoms of prostate cancer
are often similar to those of BPH, so, one of the
tests you may have at the prostate assessment
clinic is a PSA test.
What are the symptoms?
Many men with prostate cancer are unaware they
have it. It will not threaten their life, or cause any
symptoms. If we had found it, we may well have
subjected them to treatments with side effects such
as impotence and incontinence. Unfortunately, so
far, we have no way of knowing which of the
prostate cancers we find are going to be
aggressive, as opposed to ones that are not going
to cause problems.
Am I at risk of prostate cancer?
You are more at risk of prostate if your father or
your brother has had it.
What are the advantages of finding
prostate cancer?
If we find prostate cancer at an early stage
(confined within the prostate), we may be able to
cure it. We may, even if the cancer is detected
later, be able to control it and prevent it from
causing problems.
What are the disadvantages of finding
prostate cancer?
Many older men will have prostate cancer. Some
believe that 80% of men over 80 years old have
prostate cancer. Many of these men will die of old
age with their prostate cancer rather than because
of it. However, if we’d found the prostate cancer,
we may well have offered treatments. These could
cause side effects that could well affect a person’s
quality of life.
What is a PSA test?
PSA stands for Prostate Specific Antigen. It is a
protein produced in the cells of the prostate gland.
It combines with seminal fluid to assist sperm. All
men have small amounts of PSA in their
bloodstream.
Why do PSA levels rise?
Prostate biopsies
There are many reasons PSA levels in the
bloodstream rise:
We use a small needle to take several small
biopsies form the different areas of the prostate.
We send these off to our laboratory for analysis
(more information will be given to you about this
procedure if it is recommended). Sometimes this
test can cause temporary bleeding, difficulty in
passing urine and infection. To lessen the risk of
infection we prescribe antibiotics.
1) Age. Men produce more PSA as they get
older. Therefore the normal range used by
our laboratory considers the patient’s age.
2) Benign Prostatic Hypertrophy (BHP)
3) Inflammation of the prostate gland.
4) Exercise (such as cycling because of its
massaging effect on the prostate).
5) Sexual intercourse.
6) Prostate cancer.
Does a high-level of PSA mean I have
prostate cancer? Please note that PSA is
related specifically to the prostate and not
specifically to prostate cancer.
A raised PSA only tells us that you
might have prostate cancer.
It is not by itself an accurate way of
detecting the presence of prostate
cancer.
Not all prostate cancers are going to
cause problems or become lifethreatening.
PSA testing is of limited value in
discovering those cancers which need
treating.
It is important also to recognise that prostate
cancer may very occasionally be present if a
PSA is normal. This is known as a ‘false
negative test’. Around 20% of all men with
prostate cancer have a normal PSA.
What happens if my PSA level rises?
If your PSA is raised we will undertake further tests
to try to detect whether you have cancer in your
prostate.
What further tests will you perform?
Probably all of these:
Digital Rectal Examination (DRE)
At some point we will perform a digital rectal
examination. A gloved and lubricated finger is
inserted into the rectum to examine the prostate. It
is possible to detect some abnormalities of the
prostate gland in this way.
Transrectal Ultrasound Scan of the
prostate
A small probe will be placed in the rectum allowing
us to take ultrasound images of the prostate.
PSA Testing
Version 1
© Chesterfield Royal Hospital NHS Foundation Trust
Reviewed Date: June 2016
Next Planned Reviewed Date: June 2018
Directorate: Surgical
Will all these tests tell me if I have prostate
cancer?
Not necessarily.
If the laboratory detects prostate cancer in the
biopsies we send then obviously you have prostate
cancer and we can get on with treating it. However
the laboratory may well report that all the biopsies
we sent to them are negative.
Unfortunately, while this is good news, it doesn’t
mean that we can tell you that you definitely do not
have prostate cancer. There may well be a small
cancer hiding in the prostate that was not biopsied.
So, should I have a PSA test?
By now you will realise the whole issue of looking
for prostate cancer is not black-and-white. The PSA
test is by no means a perfect test to look for
prostate cancer. An increased PSA can occur when
no cancer is present; and a normal PSA does not
rule out the possibility of prostate cancer.
A raised PSA is the trigger for a series of other
tests, in particular the prostate biopsy which carries
its own problems.
A negative biopsy does not necessarily mean that
prostate cancer is not present, but the area we
have biopsied is not cancerous.
A positive biopsy, while definitely indicative of
prostate cancer, may well have found a prostate
cancer that will never cause you any problems and
does not need treating anyway. We could then find
ourselves in the position of over-treating a clinically
insignificant condition.
In conclusion then, a PSA test should not be taken
lightly. You should look at the possible risks and
benefits of the test. We are happy to spend time
talking to you about the issues surrounding the
dilemma. Only when you feel fully informed, should
you proceed.