Prostate specific antigen (PSA) levels by age: What to know

Prostate-specific antigen (PSA) is a protein made by the prostate, a walnut-shaped gland that’s part of the human male reproductive system. It is located inside the pelvis and wrapped around the urethra, the tube leading from the bladder outside the body that drains urine through the penis. 

PSA levels can be measured in the bloodstream, and elevated PSA levels can sometimes be a symptom of prostate cancer. So, this antigen gives doctors a starting point to evaluate your risk of having that disease.

But what constitutes a normal PSA level? Why might your PSA levels be elevated? And, is there such a thing as a “dangerously high” PSA level? 

Here are answers to these and three more questions I get asked frequently.

What’s a “normal” PSA level?

Doctors tend to categorize PSA levels in terms of “elevated” or “non-elevated,” rather than “normal” or “abnormal.” That’s because the range of what’s normal varies by age. Technically, someone with any PSA level can have prostate cancer; that’s not the only thing we look at when assessing a patient. 

Generally speaking, though, PSA levels for men who are:

• Age 60 or older: should be at or below 4.0 mg/mL
• Age 59 or younger: should be at or below 2.5 mg/mL

The average PSA for men in the younger group is <1.0 mg/mL.

Why are my PSA levels elevated?

Your PSA levels could be elevated for many reasons. For one thing, the size of your prostate continues to grow as you age, so that can increase the amount of antigen it releases. Other common factors that may cause elevated PSA levels include: 

• infection
• prostatitis/inflammation
• a recent urological or pelvic procedure, such as a cystoscopy or a colonoscopy
• medications, especially testosterone replacement therapy

Less common factors that may contribute to elevated PSA levels include:

• sexual activity in the last 1-2 days
• riding a bicycle, which puts pressure on the perineum

These last two are not usually the cause for elevated PSA levels in most men, though. So, urologists will typically recheck levels about a month later to confirm that nothing made them go up temporarily.

Is there a threshold PSA level that requires biopsy? 

No. But a PSA above 4.0 in anyone over age 60, or above 2.5 in anyone younger than 60, will likely prompt additional testing. 

At MD Anderson, that typically means an MRI. These scans are great, non-invasive ways of determining whether someone needs a biopsy, and, if so, what kind. We now can take samples from very specific areas that look abnormal.

What is considered a dangerously high PSA level?

Technically, there is no upper limit. PSA levels can go into the tens or even hundreds of thousands. But generally speaking, these are the ranges of elevation: 

• 4-10: minimally elevated
• 11-20: moderately elevated
• 21+: high elevation

Your doctor will likely investigate anything over 10. Anything greater than 20 starts pointing more toward cancer. Anything above 50 is usually a very strong indicator of prostate cancer. Levels that high are usually not due to an infection or some other thing going on. 

When should I start getting screened for prostate cancer, including a PSA test? 

For people at average risk, MD Anderson recommends talking with your doctor about the benefits of prostate cancer screening beginning at age 45. 

Black men and others at higher risk should start the conversation at age 40. High-risk populations include those with:

• Black heritage
• a first-degree blood relative (brother/father) who’s had prostate cancer 
• either BRCA1 or BRCA2 genetic mutations

How often should I get screened for prostate cancer? 

Generally, it’s once a year, but in some instances, it could be every two. 

If your PSA level has been stable for a long time, for instance, it might be two. But if your PSA levels have been steadily creeping up over time, you might need to get screened every six months. Everyone is different, so talk to your doctor to find out what’s best for you. 

Request an appointment at MD Anderson online or call 1-877-632-6789.