What is a normal PSA value?
Prostate-specific antigen (PSA) is a protein that is produced by both normal and cancer cells of the prostate. Your blood naturally contains small amounts of PSA.
The ‘normal’ PSA level remains a matter of debate and no clear cut-offs have been identified. Indeed, PSA levels may vary over time in the same man and may increase with age and benign diseases. Although the identification of cut-offs for PSA values is debated, the following limits have been proposed based on large studies assessing the role of PSA-based screening for early detection of prostate cancer:
- PSA levels less than 4 ng/mL are generally considered normal. However, some studies suggest that a PSA less than 1.5 ng/mL should be regarded as normal. But in both cases the PSA level should be evaluated together with the results of the digital rectal examination (DRE), age, comorbidities, concomitant medications and symptoms.
- PSA levels between 4 and 10 ng/mL are seen as suspicious but are in the ‘grey zone’. Men with a PSA level between 4 and 10 ng/mL have about a 1 in 4 chance of having prostate cancer.
- PSA levels above 10.0 ng/mL are considered elevated. If the PSA is more than 10 ng/mL, the chance of having prostate cancer is over 50%. However, PSA values can increase above the cut-off of 10 ng/ml even in patients with benign conditions such as acute prostatitis.
Of note, not all doctors use the same PSA cut-off point to decide if further tests, such as a biopsy, MRI or biomarker, are needed. Other risk factors, such as your age, the outcome of the digital rectal examination (DRE), race and family history are important in this decision.
In addition, an elevated PSA level may not only be caused by prostate cancer. Other non-cancerous conditions such as benign enlargement of the prostate (BPH), inflammation and infection of the prostate can also increase the PSA level.
Read more about your options when you have an elevated PSA.