What is the PSA test? How it detects prostate cancer and when to get screened
The prostate-specific antigen (PSA) test is a simple blood test that plays a significant role in screening for and monitoring prostate health, particularly prostate cancer—the second most common cancer among men worldwide. The test measures the level of PSA, a protein produced by both normal and malignant cells of the prostate gland, in your bloodstream.
While PSA levels can be affected by a variety of conditions—not just cancer—the test can help detect potential problems early, sometimes before any symptoms appear. But the PSA test isn’t perfect, and understanding its strengths, limitations, and the context in which it’s used is essential for making informed decisions about your health.
What Is PSA?
PSA stands for prostate-specific antigen, a protein made by the prostate gland. PSA helps liquefy semen and is normally found in low levels in the blood. However, higher-than-normal PSA levels can be a sign that something is wrong.
Normal PSA levels vary depending on age and other factors, but in general:
For men in their 40s and 50s, a PSA level under 2.5 ng/mL is considered typical.
For men over 60, PSA levels up to 4.0 ng/mL are generally acceptable.
However, there’s no universally “normal” cutoff, and trends over time often matter more than a single number.
Key Uses of the PSA Test
1. Prostate Cancer Screening
The most common use of the PSA test is to screen for prostate cancer in men without symptoms. Elevated PSA levels may suggest the presence of prostate cancer, prompting further evaluation such as imaging or a prostate biopsy.
Studies have shown that PSA-based screening can help detect prostate cancer earlier. In fact, a large European study (ERSPC) found that PSA screening reduced the risk of dying from prostate cancer by about 20% after 13 years of follow-up. However, that benefit must be weighed against the risks of overdiagnosis and overtreatment.
Screening is usually offered to men:
Aged 50 to 70, depending on overall health and life expectancy
Aged 40–45 if they have higher risk, such as:
A family history of prostate cancer (especially a father or brother)
African American ancestry (Black men are nearly twice as likely to die from prostate cancer)
2. Monitoring After Prostate Cancer Treatment
The PSA test is a critical tool for tracking prostate cancer after diagnosis or treatment. Once you’ve had prostate surgery (prostatectomy), your PSA level should drop to undetectable levels. Any measurable rise can signal a recurrence.
If you’ve undergone radiation or hormone therapy, your PSA should fall and stabilize. Your doctor will monitor:
PSA doubling time (how quickly PSA increases)
Whether the trend suggests slow growth or more aggressive disease
3. Evaluating Prostate Health in Symptomatic Men
In men experiencing urinary symptoms—such as difficulty urinating, weak stream, or frequent urination at night—PSA testing may be used alongside other diagnostic tools to assess the prostate.
Elevated PSA can be linked to:
Benign prostatic hyperplasia (BPH) – a noncancerous enlargement of the prostate
Prostatitis – inflammation or infection of the prostate
In these cases, PSA levels may be temporarily elevated and not indicate cancer.
How the PSA Test Works
The PSA test is a simple blood draw performed in a doctor’s office or lab. No special preparation is needed, but it’s best to avoid certain activities before testing:
Avoid before a PSA test:
Ejaculation (within 24–48 hours)
Vigorous exercise, especially cycling
Prostate exams or recent procedures (e.g., catheter use, biopsy)
These can falsely elevate your PSA levels.
Is PSA Testing Right for Everyone?
Not necessarily. Despite its benefits, PSA screening has its limitations, and leading medical organizations—including the U.S. Preventive Services Task Force (USPSTF)—recommend individualized decision-making.
Here’s why:
Limitations of the PSA Test
Lack of specificity: Elevated PSA levels don’t always mean cancer. BPH, infections, and even age can raise PSA.
Overdiagnosis: Some prostate cancers grow so slowly that they never cause harm. PSA screening can lead to unnecessary biopsies and treatments (like surgery or radiation), which may cause side effects such as incontinence or erectile dysfunction.
False reassurance: A normal PSA does not completely rule out cancer. Some men with prostate cancer have normal PSA levels.
Understanding PSA Velocity and PSA Density
PSA velocity: The rate of PSA increase over time. A rapid rise may indicate a higher risk of cancer.
PSA density: The PSA level relative to the size of the prostate (measured with imaging). A higher density can be a red flag.
What Happens After an Elevated PSA?
If your PSA is higher than normal, your doctor may recommend:
Repeating the test in a few weeks to confirm results
Checking for infection and treating it with antibiotics
Imaging with a prostate MRI to look for suspicious areas
Biopsy, if warranted, to determine if cancer is present
Not every elevated PSA leads to a biopsy. Doctors consider age, PSA history, risk factors, symptoms, and other lab results before taking the next step.
When to Start the Conversation
If you're a man over age 50—or younger with risk factors—it’s time to talk with your doctor about PSA testing. Even if you feel fine, early screening can help catch potential issues before they become serious.
Questions to ask your doctor:
Do I have risk factors for prostate cancer?
What are the risks and benefits of PSA testing in my case?
If my PSA is high, what would the next steps be?
Bottom Line
The PSA test is a useful tool for detecting and monitoring prostate cancer, but it’s not one-size-fits-all. Used thoughtfully—and interpreted alongside other risk factors—it can support early detection and better outcomes.
If you're unsure whether a PSA test is right for you, having a conversation with your healthcare provider is the best place to start.
Take Charge of Your Prostate Health
Bastion Health provides comprehensive virtual care for men—including PSA testing guidance, urology consultations, and follow-up support. Whether you’re managing symptoms, screening for cancer, or tracking recovery, Bastion is here to help—covered through your employer-sponsored benefits.
