PSA test - Orchid

THE PSA TEST... PROSTATE CANCER INFORMATION...
THE PSA TEST - WHAT IS IT
There is evidence that identifying people with prostate cancer
before it has spread beyond the prostate is advantageous. This
is because the cancer can be cut out surgically or radiotherapy
can be given. A proportion of these patients can be cured. One
of the problems in this area of cancer medicine is that people
with prostate cancer tend to be 65 years old or more, and the
cancer often grows slowly. Therefore proving that treatments
such as surgery are beneficial overall has been difficult and this
remains a grey area.
The PSA (Prostate Specific Antigen) gives us information on
whether there is likely to be a prostate cancer present, and
whether it has spread beyond the prostate. This is useful
information for some patients.
The PSA test measures the level of a protein made by the
prostate gland, which is increased in men with prostate cancer.
However, the level also increases with age and other causes
such as infection or non-cancerous enlargement of the
prostate (Benign Prostatic Hyperplasia). It is definitely helpful in
diagnosing prostate cancer in men over 55 years of age with
urinary symptoms or a large irregular prostate, but it has not
been proved to be of benefit as a one off screening test for
men with no symptoms.
This is because two out of three men who have a raised PSA
with no symptoms do not have prostate cancer when further
tests are performed – so the test gives a false positive. There
are even cases when a low PSA reading is recorded despite the
presence of cancer – a false negative. As a result, there is a
debate as to the utility of this test. The aim of this leaflet is to
help you decide whether or not to have the test.
THE PROSTATE GLAND
The prostate gland is only found in men, and it sits just below
the bladder (see diagram). It is about the size of a walnut and
running through it is the urethra (the tube which carries urine
and sperm out through the penis). The prostate’s job is to make
some of the fluid that helps carry sperm when men have sex.
WHAT IS KNOWN ABOUT PROSTATE CANCER
The incidence is increasing worldwide and is now the
commonest male cancer in the UK. This rise is thought to be
largely due to the increased proportion of men having PSA
tests.
The evidence of higher long term survival rates of men with
localised disease (ie whose cancer has not spread outside the
prostate) has increased the calls for earlier and more certain
means of detection, and hence an interest in PSA screening.
HOW CAN YOU TEST FOR PROSTATE CANCER
There are three main tests to check the prostate:
1. PSA Test - This is seldom useful in isolation.
2. Digital Rectal Examination - This involved the doctor
inserting a gloved finger into the rectum (back passage) to feel
the prostate. This is best at picking up advanced cancers. It can
be done by the GP in conjunction with the PSA test. It may be
uncomfortable, but it's quick and it shouldn't hurt.
3. Needle Biopsy - This is only done when cancer is suspected
THE PSA TEST
The test involves a small blood sample being taken from the
arm and usually takes up to a week to be reported back from
the laboratory to your GP.
If your PSA level is normal and if you have no symptoms of a
prostate problem (such as changes in normal urination or pain
in the groin) it is unlikely that cancer is present and no further
action need be taken. If you have symptoms further tests may
be arranged.
If your PSA level is raised, you will require further investigations.
This may include either a repeat PSA if it is only slightly raised
and the digital examination is normal; or a biopsy if the
suspicion of prostate cancer is higher.
THE DEFINITE DIAGNOSIS - A BIOPSY
Doctors can only make a definite diagnosis of prostate cancer
by taking a small sample of prostate cells though the rectum
and looking at them under a microscope. This is called a
Transrectal Needle Biopsy. Men who have this test experience
some discomfort which can be reduced using a local
anaesthetic (although sometimes the discomfort from the local
anaesthetic is as bad as the actual biopsy needle). A few men
can become very unwell afterwards due to infection.
WHAT IF I HAVE GOT PROSTATE CANCER
Although we are detecting prostate cancers earlier in the 21st
century, there is a debate about how much this is benefiting
patients. Most men with early prostate cancer will not die as a
result of prostate cancer. This is particularly true of older men
in their 70’s or 80’s. Nevertheless, there is data that shows
some patients benefit from either having the prostate cancer
removed, or having radiotherapy if the cancer has not spread
beyond the prostate.
Therefore there is no clear-cut treatment of early prostate
cancer and it depends on a number of factors. These include
whether the cancer has spread beyond the prostate, as well as
the wishes and the life expectancy of the individual.
Some of the treatments have side effects such as urinary
incontinence or impotence. Therefore some people choose to
have a large operation to remove the prostate, while others
opt for a more conservative approach, where the PSA level is
monitored for change. You should discuss all these options with
the specialist doctors.
SO, SHOULD I HAVE THE PSA TEST
Possible advantages of having a PSA test
• It may be reassuring if it is normal.
• It can find cancers earlier than is possible by a finger
examination of the back passage.
• Treatment at early stages may help you live longer although
this has not been conclusively proved yet.
Possible disadvantages of having a PSA test are
• It may lead to anxiety if the result indicates that PSA is
raised although you don’t have cancer.
• If you have got cancer, the test can’t tell you if it’s likely to
cause you problems in the future.
• Cancer can sometimes be present when the PSA test
result is lower than in a man without cancer.
• There is no good evidence that identifying prostate
cancers earlier helps people live longer.
• Treatments for early prostate cancer carry about a one in
three risk of incontinence and impotence.
There is no right or wrong answer when it comes to having a
PSA test. People deal with this uncertainty in different ways.
Some men choose to be uncompromising in looking for, and
treating, early prostate cancers. Others may not even want to
know if they have an early prostate cancer because they think
that, on balance, having that information would do them more
harm than good. With the help of your doctor, and this leaflet,
you need to make the right decision for you.