Prostate Cancer, PSA and Outcomes
The Role of PSA in Men with Prostate Cancer
PSA is not a reliable measure of prostate cancer before a man is diagnosed. However, once you have been diagnosed and have received a primary treatment, the PSA test becomes one of the best available surrogate measures of your cancer’s progress or decline.
Your PSA measure is now your best friend.
Always know your PSA number. Plot your PSA on a graph so that you can see changes in its trend and calculate your PSA velocity (how fast it is changing) and PSA doubling time. For men with advanced prostate cancer, we recommend that you have a PSA test at least every three (3) months. The more points you can graph, the more useful the graph will become. Also, we believe that PSA anxiety (the fear some men experience prior to learning their PSA results) is reduced by frequent PSA tests. The sooner you can determine changes in your PSA, the sooner and more effectively you and your medical team can adjust your treatment. Show your PSA graph to your doctor at every visit and ask about the meaning of your graphic representation of your PSA—especially any changes in PSA value.
What is the PSA test?
The PSA test is a blood test that measures the total amount of prostate specific antigen (PSA) in your blood. PSA is a protein produced by normal cells in the prostate and also by prostate cancer cells. It is normal for all men to have a small amount of PSA in their blood. An elevated PSA level may show that you have a
problem with your prostate, but not necessarily prostate cancer.
The three most common types of prostate problems are:
• Non-cancerous enlargement of the prostate called benign prostatic hyperplasia (BPH)
• An inflammation or infection of the prostate gland called prostatitis
• Prostate cancer
Who can have a PSA test?
All men are entitled to have a PSA test. These days, most doctors will first talked through the pros and cons of taking a PSA test. What possible “cons” might there be? Well, many elevated PSA levels indicate things other than cancer. And, even a positive biopsy may point to a prostate cancer that may not kill you. Remember, the treatments for prostate cancer include the risk of impotence, incontinence and later, secondary cancers. No one should be treated who does not need treatment. Unfortunately, we do not have a test to determine whose life is at risk by prostate cancer.
Should I have a PSA test?
Deciding on whether or not to have a PSA test is a personal choice and you might like to talk this over with your partner, family or friends. You might decide
to go to your GP if you have some urinary symptoms, are worried about prostate problems, or because you feel that you might be more at risk of developing prostate cancer. If you are over the age of 35, your internist or family doctor may suggest that you get a check-up andhave a number of different tests, including a PSA test.
Your internist, local health clinic and even community health fair can likely offer you a PSA test.
Before you have a PSA test
You should let your GP know if you are taking any prescription or over-the-counter medication as this might also affect your PSA test results.
Your doctor may give you advice about what else could affect the PSA level.
• It may help to pick up a significant prostate cancer before you get any symptoms.
• The test could help to monitor men who have a higher risk of developing prostate cancer.
• It may help to pick up a more aggressive cancer at an early stage when treatment may prevent the cancer from becoming more advanced.
• Repeat PSA tests can identify changes to your PSA level that may show that there is a problem with your prostate.
• It may help to pick up a non-cancerous prostate problem such as BPH or prostatitis which can be treated and may relieve you of any symptoms.
• Around two thirds of men with a raised PSA do not have prostate cancer.
• It will not pick up all prostate cancers. Some men with prostate cancer have a normal PSA level.
• It cannot tell you whether a prostate cancer is likely to be fast or slow growing (high or low risk). A slow growing cancer may not cause any symptoms or shorten your life.
• If your PSA is raised, you may need a biopsy which some men find uncomfortable and has some risks.
• Treatment for prostate cancer may cause significant side effects which can affect your daily life.
Things that could affect your PSA level include:
A urine infection
Your doctor will test your urine for infection. Your doctor will treat any infection and give you the PSA test in four to six weeks time.
Exercise such as cycling may raise the PSA level. You might be asked not to do any vigorous exercise in the 48 hours before a PSA test.
Any sexual activity that results in ejaculation in the 48 hours before a PSA test may raise the PSA level.
If you have had a prostate biopsy in the six weeks before a repeat PSA test, this could raise the PSA level.
If you have a catheter or have had any investigations or operations on your bladder or prostate, these can raise your PSA level. Your specialist may suggest waiting for up to six weeks after these procedures before having a PSA test.
If possible, a Digital Rectal Exam should be after rather than before a PSA test. Having a DRE right before a PSA test may raise your PSA level.
What will the test results tell me?
A PSA test alone cannot tell you whether you have prostate cancer. PSA naturally rises as men get older, as the prostate gland gets bigger and may produce more PSA. A high PSA level for your age can be a sign of prostate cancer, but it can be caused by non-cancerous enlargement of the prostate (benign prostatic hyperplasia) or an infection or inflammation of the prostate (prostatitis).
PSA levels can range from 1ng/ml to up into the 100s and further. The following figures are a rough guide to ‘normal’ PSA
levels, depending on your age:
• Up to 3 ng/ml for men in their 50s
• Up to 4 ng/ml for men in their 60s
• Up to 5 ng/ml for men in their 70s and over
A very high PSA level (for example in the 100s) normally means that a man has prostate cancer. However, if your PSA level is only slightly above the normal range for your age, then your doctor cannot tell as much from the result and would normally need to do other tests to help find out if there is a problem.
Your doctor will also look at any history of previous PSA tests that you might have had. The difference between two or more PSA tests, divided by time, is called the PSA velocity. Significant velocity might also raise a red flag for you.
PSA tests were first used to gauge the success of prostate cancer treatment.
The prostate is the source of PSA. After surgical removal of the prostate, PSA levels can be expected to fall. If PSA still can be detected, it suggests that some prostate cells still may be present somewhere in the body. If, sometime in the future, the PSA level begins to rise, it may be the first sign of recurrence. Such a biochemical relapse typically precedes clinical relapse-symptoms-by months or years. However, it is not known if treatment should start again or change based solely on a rise in PSA.
Now research suggests that pretreatment PSA levels may provide another important clue to prognosis, independent of stage and grade. In one study, nearly 90 percent of the men with a low pretreatment PSA level (4 ng/ml or less) remained free of any signs of relapse (either symptoms or a rising PSA level) 5 years after surgery. But among men with a high preoperative PSA level (20 ng/ml or higher), just one-quarter remained relapse-free.
For men who have not been treated for prostate cancer, the Digital Rectal Exam should always be done after drawing blood for the PSA test.