PSA Screening Test: Purpose, Results, Benefits, and Risks
Updated on October 08, 2026
ON THIS PAGE
ON THIS PAGE
Though most cases of prostate cancer have a good prognosis, the disease is the second leading cause of cancer deaths in American men.
As with other cancers, it’s best to detect prostate cancer at an early stage, when treatment may be more effective and elicit fewer, less severe side effects. The most common screening test for prostate cancer is a prostate-specific antigen (PSA) blood test, which measures the levels of the PSA enzyme in the blood.
What Is PSA?
The prostate is a walnut-sized gland, situated between the bladder and penis, that’s part of the male reproductive system. Its main function is to produce fluid that partly makes up semen, which helps transport and protect sperm produced by the testicles.
The prostatic fluid contains various substances that help sperm cells function and survive. One of these substances is PSA.
PSA thins or loosens up semen, allowing sperm cells to swim freely while in the female body. Some of the PSA produced by prostate cells also makes its way into the blood.
A person’s PSA levels increase with age — likely an evolutionary adaptation that allowed those with this trait to sire more offspring than other males.
What Is a PSA Screening Test?
A PSA screening blood test measures the levels of PSA circulating in the blood.
Both normal prostate cells and cancer cells make PSA. While prostate cancer cells tend to produce less PSA than normal cells, they allow PSA to more easily pass through the cell wall and eventually wind up in the bloodstream.
This suggests that elevated PSA levels in the blood could signify prostate cancer.
The U.S. Food and Drug Administration initially approved the PSA blood test to be used as a screening tool to aid in the detection of prostate cancer in men 50 years or older. Current clinical practice guidelines from the National Comprehensive Cancer Network (NCCN) and American Urology Association (AUA) now recommend offering baseline screening as early as age 45 for men at average risk.
High-risk individuals include Black men, men with a family history of prostate cancer, and those with inherited genetic mutations (such as the BRCA gene). Those at high risk might want to start screening sooner.
Both the NCCN and AUA emphasize shared decision-making, meaning that doctors and their patients should talk through the patient’s values, risk factors, and preferences before the PSA test, as opposed to making it an automatic screening for everyone.
What’s a Normal PSA Level?
Most healthy men have PSA levels in the blood of less than 4 nanograms per milliliter (ng/mL). The chances of having prostate cancer go up as PSA concentrations increase.
That said, some men with low PSA levels (below 4 ng/mL) have gotten prostate cancer, while others with high PSA levels (between 4 ng/mL and 10 ng/mL) have not. This is partly because various other factors can affect PSA production and test results.
Long-term factors that can increase PSA levels include:
- Prostatitis, or prostate inflammation
- Enlarged prostate
- Older age
- Urinary infection
Recent ejaculation, anal sex, or even a long bike ride can also temporarily cause high PSA levels.
Additionally, obesity and certain medications — finasteride (Propecia) and dutasteride (Avodart), which are used to treat enlarged prostate — can lower PSA levels.
Given the uncertainties around PSA test results, only a prostate biopsy (removal of prostate tissue for analysis) can actually diagnose prostate cancer.
Benefits and Risks of PSA Screening
The PSA blood test was used for annual prostate cancer screenings until about 2008, when scientists learned more about its benefits and harms. A controversy bloomed as experts tried to determine whether the benefits of annual prostate cancer screenings outweighed the risks.
The main issue is that a PSA blood test cannot differentiate between benign (noncancerous) and malignant (cancerous) tissue. Therefore, a high PSA test result could cause considerable unnecessary anxiety, if the man doesn’t have prostate cancer. Additionally, many slow-growing prostate cancers may not need treatment, which can cause side effects such as impotence, incontinence, and bowel issues.
In 2012, the U.S. Preventive Services Task Force (USPSTF), an independent panel of experts that makes evidence-based recommendations about clinical preventive services, found little benefit and significant harm associated with routine PSA blood tests to screen for prostate cancer. It subsequently recommended against these tests.
The USPTF updated its recommendation in 2018 to reflect new evidence of the benefits of PSA screenings on prostate cancer death rates. For men 55 to 69 years old, it recommends making a joint decision with your doctor about whether to undergo periodic PSA screening, after discussing the risks and benefits of screening.
The USPSTF recommends against prostate cancer screening in men over 70, but the NCCN suggests that at this age, screening could be considered if the person is expected to live for at least another 10 years.
Many other professional healthcare organizations, associations, and societies have similar recommendations for prostate cancer screening.
PSA testing is thought to lower cancer mortality rates, and the mortality rate of prostate cancer has significantly declined over the past 30 years.
If Your Test Shows High PSA Levels
If a PSA screening blood test shows slightly elevated PSA values, your doctor may recommend another PSA test within a few months. If you have two abnormal PSA values and a reasonable life expectancy of at least 10 years, your doctor may recommend a prostate biopsy to confirm whether you have prostate cancer.
Your doctor may also recommend a biopsy if you have:
- A family history of prostate cancer, multiple cancers, or Lynch syndrome
- African descent
- A quick rise in PSA levels over a year
- Abnormal lumps found during a digital rectal exam
Active Surveillance
In many cases, prostate cancer grows slowly, so some men who have it may never need treatment. Rather than unnecessarily treating a slow-growing cancer, your doctor may recommend active surveillance, if you have low-risk cancer.
Men who undergo treatment do not appear to live longer than those who undergo active surveillance.
During active surveillance, PSA is used as a biomarker, meaning that PSA levels are measured periodically to keep track of the severity and progression of the cancer. You may need to get a PSA test every three to six months, a digital rectal exam once every year, and biopsies and imaging tests every one to three years.
Magnetic resonance imaging tests may also be done to determine the risk level of specific cases of prostate cancer.
Treatment is considered only if your cancer is growing quickly or becoming aggressive. If you are being treated for prostate cancer, PSA may also be used as a biomarker for how well the treatment is working.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
- Key Statistics for Prostate Cancer. American Cancer Society. January 13, 2026.
- David MK et al. Prostate-Specific Antigen. StatPearls. September 10, 2024.
- Prostate. Cleveland Clinic. November 24, 2025.
- Prostate-Specific Antigen (PSA) Test. National Cancer Institute. January 31, 2025.
- Prostate Cancer Screening. National Comprehensive Cancer Network. 2026.
- Lin DW et al. Updates to Early Detection of Prostate Cancer: AUA/SUO Guideline (2026). American Urological Association. May 1, 2026.
- Prostate-Specific Antigen (PSA) Blood Test. MedlinePlus. February 3, 2025.
- The PSA Blood Test. Prostate Cancer UK. January 2025.
- Prostate Cancer: Screening, 2008. U.S. Preventative Services Task Force. August 5, 2008.
- Observation or Active Surveillance for Prostate Cancer. American Cancer Society. September 11, 2026.
- Prostate Cancer: Screening. U.S. Preventive Services Task Force. May 5, 2012.
- Prostate Cancer: Screening. U.S. Preventive Services Task Force. May 8, 2018.
- Cancer Stat Facts: Prostate Cancer. National Cancer Institute.
- Wise J. PSA Screening Cuts Cancer Mortality by 13%, Study Shows, Amid Debate About National Programme. BMJ. October 30, 2025.
Meet Our Experts
Christopher Wolter, MD
Medical Reviewer
Christopher Wolter, MD, is an assistant professor in urology at Mayo Clinic in Phoenix, Arizona. He has been in practice since 2008, specializing in the areas of urinary incontinen...
Joseph Bennington-Castro
Author
Joseph Bennington-Castro is a science writer based in Hawaii. He has written well over a thousand articles for the general public on a wide range topics, including health, astronom...