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• The PSA test

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 information is to help you decide whether or not to have the test.

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.

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.

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