Health News, Information and Advice from a British Doctor
Prostate Specific Antigen Test (PSA Test)
Prostate gland is only found in men, it sits below your bladder and makes seminal fluid released during ejaculation. Prostate Specific Antigen (PSA) is a protein produced by the prostate gland and is normally present in your blood. PSA level can be elevated in certain medical conditions affecting the prostate. A PSA test is essentially a blood test that measures PSA level in your blood.
Prostate Cancer is the most common cancer in men in the UK, and it is estimated that 1 in 8 men will get it at some point in their lifetime. PSA level in the blood is increased in prostate cancer. As early prostate cancer is usually symptomless, PSA test may help detect prostate cancer before any warning signs appear. However, PSA test is not specific for prostate cancer, thus it is not used as a national screening programme in the UK. Studies reveal that 2 out of 3 men with raised PSA level will NOT have prostate cancer. PSA level in your blood can be raised in:
- Prostate infection or inflammation (prostatitis)
- Enlarged prostate (benign prostatic hyperplasia)
- Urinary tract infection (UTI)
Recent sexual intercourse, heavy exercise or medical examination of the prostate can also give slightly raised PSA result.
Prostate grows in size during a man’s lifetime and changes in prostate do not necessarily mean cancer. It is also known that many slow-growing cancers may not be life-threatening, as many men will have some cancer cells present in their prostate by the age of 80, but only 1 in 25 will die from it.
PSA test is not reliable enough to be used to check for prostate cancer in symptomless men and it cannot distinguish between slow and fast-growing cancers. It is believed that many men would get false positive PSA test results and go through unpleasant prostate examinations and biopsies. In addition, a false positive test result can cause emotional distress to the man and his family.
PSA test can also lead to the diagnosis of slow-growing cancers that would never cause any health problems. Therefore, some men may receive costly prostate cancer treatment with numerous unwanted effects such as erectile and bladder dysfunction, even though they do not really need it.
Nevertheless, a PSA test may be useful in men with higher risk of prostate cancer because PSA test may be the only way to diagnose it early. Early diagnosis can prolong life in some patients and prevent the symptoms of advanced cancer. It is believed you are at higher risk of prostate cancer if you are:
- Over 50 years of age and the risk increases with age
- Have a brother or a close family relative who had prostate cancer before the age of 60
- Are of Black-African or Black-Caribbean origin
- Your mother or sister had breast cancer caused by faulty breast cancer genes (BRCA1 or BRCA2 mutations)
If you are worried that you may be at higher risk of prostate cancer and would like to have a PSA test, you can arrange to do it for free with your GP as part of the Prostate Cancer Risk Management Programme. As many activities can lead to an unreliable PSA test result, if you decide to have the test it is important that you do not have:
- Active urinary tract infection
- Exercised or ejaculated in the past 48h
- Had a digital rectal examination in the last week
- Had a prostate biopsy in the last 6 weeks
If you have raised PSA level, you will need to have further tests to examine your prostate, as PSA test alone is NOT sufficient to diagnose prostate cancer. These tests include digital rectal examination (DRE) and a prostate biopsy. In a digital rectal examination your doctor will insert a gloved finger into your rectum and feel for the prostate, in case of cancer the prostate looses elasticity and feels hard. Prostate biopsy involves inserting needles into the prostate and taking tissue samples for laboratory analysis under the microscope. Prostate biopsy is not perfect and may still miss some cancers, but is currently the gold standard for prostate cancer diagnosis. It is required to confirm prostate cancer after a raised PSA test. If you do have prostate cancer, you will discuss the treatment options with your doctor. Sometimes the treatment is delayed until you start feeling ill or there is a risk cancer may spread to other organs. Different therapies are available including radiotherapy, surgery and hormone therapy. Your doctor will help you make an informed decision on the most appropriate course of action.
If your PSA test is slightly raised, you may want to repeat the test after 2-3 months. On the other hand, if your PSA test is not elevated, you can be confident your prostate is in good health and you do not need to do the test for the next 2 years.
Researchers are currently trying to improve PSA tests. Many doctors believe that if PSA test could measure both PSA level in the blood and relative PSA level increase, then it could be used as a reliable way to test for prostate cancer. At the moment it is simply not accurate enough.
If you are unsure whether or not to have the test, keep in mind that the average age range for prostate cancer is 70-74, and that symptoms appear only at a later stage. Symptoms include increased need to urinate and a weaker flow of urine, but these are NOT specific for prostate cancer. PSA test is not a very good test. However, it can reassure you that your prostate is in good health if your PSA level is not elevated. Therefore, if you are very concerned about prostate cancer, you may want to consider having a PSA test.