What is Prostate-Specific Antigen (PSA) Test?
A prostate-specific antigen (PSA) test measures the level of PSA in your blood. The prostate is a small gland that is part of a man’s reproductive system. It is located below the bladder and makes a fluid that is part of semen. PSA is a substance made by the prostate. Men normally have low PSA levels in their blood. A high PSA level may be a sign of prostate cancer, the most common non-skin cancer affecting American men. But high PSA levels can also mean noncancerous prostate conditions, such as infection or benign prostatic hyperplasia, a noncancerous enlargement of the prostate.
Why is Prostate-Specific Antigen (PSA) Test performed?
A PSA test is used to screen for prostate cancer. You may get a PSA test if you have certain risk factors for prostate cancer. These include:
- A father or brother with prostate cancer
- Being African-American. Prostate cancer is more common in African-American men. The reason for this is unknown.
- Your age. Prostate cancer is more common in men over the age of 50.
You may also get a PSA test if:
- You have symptoms such as painful or frequent urination, and pelvic and/or back pain.
- You’ve already been diagnosed with prostate cancer. The PSA test can help monitor the effects of your treatment.
What should I know before receiving Prostate-Specific Antigen (PSA) Test?
Professional organizations vary in their recommendations about who should — and who shouldn’t — get a PSA screening test. Discussing with your doctor the benefits, limitations and potential risks of the PSA test can help you make an informed decision.
Benefits of the test
A PSA test may help detect prostate cancer at an early stage. Cancer is easier to treat and is more likely to be cured if it’s diagnosed in its early stages.
But to judge the benefit of the test, it’s important to know if early detection and early treatment will improve treatment outcomes and decrease the number of deaths from prostate cancer.
A key issue is the typical course of prostate cancer. Prostate cancer usually progresses slowly over many years. Therefore, a man may have prostate cancer that never causes symptoms or becomes a medical problem during his lifetime.
Limitations of the test
The limitations of PSA testing include:
- PSA-raising factors. Besides cancer, other conditions that can raise PSA levels include an enlarged prostate (benign prostatic hyperplasia, or BPH) and an inflamed or infected prostate (prostatitis). Also, PSA levels normally increase with age.
- PSA-lowering factors. Certain drugs used to treat BPH or urinary conditions, and large doses of certain chemotherapy medications, may lower PSA levels. Obesity can also lower PSA levels.
- Misleading results. The test doesn’t always provide an accurate result. An elevated PSA level doesn’t necessarily mean you have cancer. And many men diagnosed with prostate cancer have a normal PSA level.
- Studies have estimated that between 23 and 42 percent of men with prostate cancer detected by PSA tests have tumors that wouldn’t result in symptoms during their lifetimes. These symptom-free tumors are considered overdiagnoses — identification of cancer not likely to cause poor health or to present a risk to the man’s life.
The potential risks of the PSA test are essentially related to the choices you make based on the test results, such as the decision to undergo further testing and treatment for prostate cancer. The risks include:
- Biopsy issues. A biopsy is a procedure that carries its own risks, including pain, bleeding and infection.
Psychological effects. False-positive test results — high PSA levels but no cancer found with biopsy — can cause anxiety or distress. If you are diagnosed with prostate cancer, but it appears to be a slow-growing tumor that doesn’t
How to prepare for Prostate-Specific Antigen (PSA) Test?
You will need to avoid having sex or masturbating for 24 hours before your PSA test, as releasing semen can raise your PSA levels.
What happens during Prostate-Specific Antigen (PSA) Test?
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
What happens after Prostate-Specific Antigen (PSA) Test?
This test doesn’t require any special aftercare. You may resume your daily activities unless instruced otherwise by your doctor.
If you have any questions about the Prostate-Specific Antigen (PSA) Test, please consult with your doctor to better understand your instructions.
Explanation of results
What do my results mean?
There is no specific normal or abnormal level of PSA in the blood, and levels may vary over time in the same man. In the past, most doctors considered PSA levels of 4.0 ng/mL and lower as normal. Therefore, if a man had a PSA level above 4.0 ng/mL, doctors would often recommend a prostate biopsy to determine whether prostate cancer was present.
However, more recent studies have shown that some men with PSA levels below 4.0 ng/mL have prostate cancer and that many men with higher levels do not have prostate cancer. In addition, various factors can cause a man’s PSA level to fluctuate. For example, a man’s PSA level often rises if he has prostatitis or a urinary tract infection. Prostate biopsies and prostate surgery also increase PSA level. Conversely, some drugs—including finasteride and dutasteride, which are used to treat BPH—lower a man’s PSA level. PSA level may also vary somewhat across testing laboratories.
Another complicating factor is that studies to establish the normal range of PSA levels have been conducted primarily in populations of white men. Although expert opinions vary, there is no clear consensus regarding the optimal PSA threshold for recommending a prostate biopsy for men of any racial or ethnic group.
In general, however, the higher a man’s PSA level, the more likely it is that he has prostate cancer. Moreover, a continuous rise in a man’s PSA level over time may also be a sign of prostate cancer.
If a man who has no symptoms of prostate cancer chooses to undergo prostate cancer screening and is found to have an elevated PSA level, the doctor may recommend another PSA test to confirm the original finding. If the PSA level is still high, the doctor may recommend that the man continue with PSA tests and DREs at regular intervals to watch for any changes over time.
If a man’s PSA level continues to rise or if a suspicious lump is detected during a DRE, the doctor may recommend additional tests to determine the nature of the problem. A urine test may be recommended to check for a urinary tract infection. The doctor may also recommend imaging tests, such as a transrectal ultrasound, x-rays, or cystoscopy.
If prostate cancer is suspected, the doctor will recommend a prostate biopsy. During this procedure, multiple samples of prostate tissue are collected by inserting hollow needles into the prostate and then withdrawing them. Most often, the needles are inserted through the wall of the rectum (transrectal biopsy). A pathologist then examines the collected tissue under a microscope. The doctor may use ultrasound to view the prostate during the biopsy, but ultrasound cannot be used alone to diagnose prostate cancer.
Depending on the laboratory and hospital, the normal range for Prostate-Specific Antigen (PSA) Test may vary. Please discuss with your doctor any questions you may have about your test results.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Prostate-Specific Antigen (PSA) Test. https://www.cancer.gov/types/prostate/psa-fact-sheet#q3. Accessed October 25, 2018.
Prostate-Specific Antigen (PSA) Test. https://medlineplus.gov/lab-tests/prostate-specific-antigen-psa-test/. Accessed October 25, 2018.
PSA test. https://www.mayoclinic.org/tests-procedures/psa-test/about/pac-20384731. Accessed October 25, 2018.
Review Date: November 5, 2018 | Last Modified: November 5, 2018