Prostate Specific Antigen (PSA)
What is PSA?
PSA, short for Prostate Specific Antigen, is one of three major factors considered when evaluating whether a man has prostate cancer. The word “specific” means that this enzyme is produced only by prostate cells—whether normal prostate cells or prostate cancer cells. No other cells in the body (lung, intestine, liver, etc.) make PSA. The purpose of PSA is to keep semen (the white substance ejaculated during sexual intercourse) liquefied. PSA is also leaked into the bloodstream by normal prostate cells and can be measured by a simple blood test.
PSA and Its Role in Identifying Prostate Cancer
A prostate cancer cell typically makes a lot more PSA than a normal prostate cell. Usually, but not always, the amount of PSA you have indicates how much cancer you have. Benign (not cancerous conditions) like benign prostate hypertrophy (enlarged prostate) can also increase your PSA. However, the amount of PSA does not always show how much cancer you have. When prostate cancer is found in a biopsy, the average PSA level is 7.4 ng/ml. Sixty-two percent of men with prostate cancer have PSA between 4.1 and 10, although it can also be lower or higher than these levels. Men with “normal” PSA have been found to have prostate cancer as well.
PSA Testing Recommendations Have Changed. What You Need to Know?
Your best defense against prostate cancer is the PSA test which can lead to early detection, a critical part of being successfully treated. Recommendations for initiating testing for elevations or changes in PSA vary based on age, medical history and ethnicity. Current recommendations to start PSA testing include:
All Men over the age of 50
African American men 45 years old, or older
Men with a family history of prostate cancer at age 40
The standard recommendation for routinely checking a man’s PSA has changed due to the finding that most men with an elevated PSA do not have prostate cancer. The American Cancer Society has issued the following recommendation for PSA testing:
Conduct the first test according to the man’s age for prostate cancer screening. Then use the following guidelines:
PSA test shows less than 2.5 ng/mL may only need to be retested every 2 years.
Annual PSA test for men whose level is 2.5 ng/mL or higher.
The PSA test may not be perfect, but it gives men the best chance of detecting prostate cancer early and more time to seek appropriate management before giving cancer a chance to spread. PSA testing is covered by Medicare as well as most private insurance carriers.
Finding the Right Prostate Cancer Treatment Plan for You
The most important piece of information a man should know about prostate cancer is that a zero PSA (<0.2) reading 15 years after any treatment is what is commonly considered the gold standard to show cure and is the key to deciding what treatment to undergo. Many doctors talk about treatment but ignore discussing how well that treatment cures. But isn’t the goal to be cured?
There are at least 12 different treatments for prostate cancer, and they vary greatly in how well they can provide a potential cure. Radiotherapy Clinics of Georgia physicians specialize in curing prostate cancer and can give men their own Individual Cure Rate (ICR), which is the percentage that represents the likelihood of completely curing a man’s unique prostate cancer. Based on years of data (made up of millions of data points) collected from more than 16,000 men before, during, and after treatment, ProstRcision’s database is unmatched by any other cancer treatment center in America.
We encourage men recently diagnosed with prostate cancer to contact us to learn more about their diagnosis.
Get Your FREE Prostate Cancer Guidebook
Make an informed prostate cancer treatment decision. Our 40-page, comprehensive guidebook provides answers to our most frequently asked questions from men diagnosed with prostate cancer, and compares various treatment methods, cure rates and side effects. Our team can also connect you with one of our oncologists at no cost.
Frequently Asked Questions about PSA and Prostate Cancer
My PSA is 4.4. Is that considered high?
PSA stands for Prostate Specific Antigen. The word ‘Specific’ means that this enzyme is produced only by prostate cells – whether normal prostate cells or prostate cancer cells. No other cells in the body – lung, intestine, liver, etc. – make PSA. The purpose of PSA is to keep semen (the white substance ejaculated during sexual intercourse) liquefied. PSA is also leaked into the bloodstream by normal prostate cells and can be measured by a simple blood test as was done with your PSA. PSA tests vary based on each person and testing numbers can be unique to an individual. This means that while a 4.4 PSA could be high for one person, it may be normal, or even low for somebody else.
What is the usual amount of PSA in the bloodstream made by normal prostate cells?
Researchers and doctors used to think that a PSA below 4.0 was normal. Now, with more experience, we recognize that there is no such thing as a normal PSA. Most men who do not have prostate cancer will have a PSA below 2.0. However, you can have cancer with a PSA below 2.0. On the other hand, as men age and the prostate becomes enlarged by more normal cells, more PSA is produced. Because of this, most men with a PSA below ten do not have prostate cancer.
What happens to a man’s PSA when he gets cancer?
A prostate cancer cell typically makes a lot more PSA than a normal prostate cell. As a result, the PSA levels will increase in response to the presence of cancer. However, the amount of PSA does not always show how much cancer you have. Sometimes cancer cells don’t make much PSA. We have seen men with PSA below 1.0 with prostate cancer.
What is the average PSA level when prostate cancer is found in a biopsy?
The average is 7.4 ng/ml. So, a PSA below 7.4 suggests a person has less cancer than average. Men with prostate cancer are divided into different groups based on their PSA levels. Tests on PSA levels will be critical for an urologist to determine if other tests or a biopsy may be necessary. The results of these tests can help your medical team determine the best course of treatment for a patient.
If most men with a PSA below ten do not have prostate cancer, but most men with prostate cancer also have a PSA below 10, how do you know if a man’s PSA rise is from cancer or not?
You don’t. This is the limitation of the PSA test. An elevated PSA can be produced by prostate cancer, but it also can be produced by other causes such as benign prostate hyperplasia (enlargement of the prostate or BPH) and prostatitis (irritation or inflammation of the prostate). In fact, most elevated PSAs are not due to cancer but are due to BPH (Benign prostatic hyperplasia) or prostatitis. To be sure, more tests may be run by your urologist to determine if there is a condition that needs to be treated.
How did my doctor know what was causing my PSA to go up?
Without further testing, the doctor can’t tell the reason for an elevated PSA. There is no way to determine why your PSA is elevated except through a prostate biopsy. That is often the next step in evaluating whether prostate cancer is the reason for the increased PSA.
Does PSA tell you where the cancer cells are located? If I had prostate cancer cells in my left shoulder bones, would those cancer cells make PSA?
Yes, a prostate cancer cell in your left shoulder could make the same amount of PSA as a cancer cell in your prostate. PSA gives no indication of where the cancer cells are located in your body. For example, let’s say with your PSA of 4.4 that you have 100 cancer cells in your body producing PSA. If all 100 cells are located inside your prostate, your PSA would be 4.4. If 90 were inside the prostate and ten had leaked outside the prostate into your left shoulder, you would still have a PSA of 4.4. PSA does not show where cancer cells are located in your body.
I have a weak, slow stream. If I did not get a PSA test, would my urine symptoms cause my doctor to check for cancer?
No. Prostate cancer rarely causes any urine symptoms. The urinary symptoms you are having are probably from compression (squeezing) of the urethra due to an enlarged prostate, called BPH. The first symptom of prostate cancer is usually bone pain from cancer cells that have spread to the bone, such as your spine, and then you are not curable.
If I quit doing a PSA test, could my primary care doctor find prostate cancer early by my yearly physical exam?
Not likely. Most men who have prostate cancer have a normal prostate exam. Prostate cancer is usually more advanced when it is found during a physical exam.
I have heard that men often die of something else and not because of their prostate cancer. Is that true?
That certainly happens. If you were to die of a heart attack in the next few years, doctors and insurance companies against PSA testing would say: This man had prostate cancer but died of something else, which shows that the PSA test was needless. However, what happens if you don’t die of a heart attack? By staying trim, exercising, and not smoking, you can live for 20 or more years. Thus, you could live long enough to die because of your prostate cancer. From the time of biopsy, the average time to death for men who die because of prostate cancer is eight years but can range from less than a year to 25 or more years later.