Measuring the PSA level can increase the chance of finding prostate cancer when it is very early. But there is debate over the value of the PSA test for detecting prostate cancer. No single answer fits all men.
Before having the test, talk to your provider about the pros and cons of having a PSA test. Ask about:
Whether screening decreases your chance of dying from prostate cancer.
Whether there is any harm from prostate cancer screening, such as side-effects from testing or overtreatment of cancer when discovered.
If you choose to be tested, the PSA is most often done every year to screen men:
From ages 55 to 69, if no risk factors are present.
Starting around age 40 to 45 if they have a higher chance of developing prostate cancer. A family history of prostate cancer (especially a brother or father) and being African-American are more common risk factors.
The PSA test result cannot diagnose prostate cancer. Only a prostate biopsy can diagnose this cancer.
Your provider will look at your PSA result and consider your age, ethnicity, medicines you are taking, and other things to decide whether your PSA is normal and whether you need more tests.
A normal PSA level is considered to be 4.0 ng/mL (nanograms per milliliter of blood).
For men in their 50s or younger, a PSA level should be below 2.5 in most cases.
Older men often have slightly higher PSA levels than younger men.
What Abnormal Results Mean
A high PSA level has been linked to an increased chance of having prostate cancer.
PSA testing is an important tool for detecting prostate cancer, but it is not foolproof. Other conditions can cause a rise in PSA, including:
A larger prostate
Prostate infection (prostatitis)
Urinary tract infection
Recent tests on your bladder (cystoscopy) or prostate (biopsy)
Catheter tube recently placed into your bladder to drain urine
Recent intercourse or ejaculation
Your provider will consider the following things when deciding on the next step:
If you had a PSA test in the past and how much and how fast your PSA level has changed
If a prostate lump was found during your exam
Other symptoms you may have
Other risk factors for prostate cancer, such as ethnicity and family history
Men at high risk may need to have more tests. These may include:
Repeating your PSA test, most often sometime within 3 months
A prostate biopsy
A follow-up test called a free PSA (fPSA). The lower the level of this test, the more likely it is that prostate cancer is present.
A urine test called PCA-3
If you have been treated for prostate cancer, the PSA level can show if treatment is working or if the cancer has come back. Often, PSA level rises before there are any symptoms. This may happen months or years beforehand.
Slight risks associated with having blood drawn may include:
Fainting or feeling light-headed
Hematoma (blood accumulating under the skin)
Infection (a slight risk any time the skin is broken)
National Cancer Institute. Prostate Cancer Screening. (Health Professional version) April 2, 2015. www.cancer.gov/cancertopics/pdq/screening/prostate/HealthProfessional/. Accessed April 26, 2015.
U.S. Preventive Services Task Force. Screening for prostate cancer. www.uspreventiveservicestaskforce.org/prostatecancerscreening/prostatefinalrs.htm. Accessed April 20, 2015.
Jennifer Sobol, DO, Urologist at the Michigan Institute of Urology, West Bloomfield, MI. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.