Percent Free PSA (% Free PSA)
Here’s what it reflects — and what to do about it.
Longetic pulls together every lab and record you’ve had, follows how Percent Free PSA (% Free PSA) changes over time, and explains what’s shifting — so you walk into your next appointment prepared, with reminders for retests along the way.
What is Percent Free PSA (% Free PSA)?
The share of your total PSA that is in the unbound (free) form, used to help judge the chance that an elevated PSA is due to cancer.
Percent-free PSA is a calculation, free PSA divided by total PSA expressed as a percentage, used mainly in men who already have an elevated total PSA. A lower percentage can be associated with a higher chance that prostate cancer is present, which can help a man and his doctor decide whether to proceed to biopsy. It is a supporting piece of information, not a diagnosis, and applies only to men. Because it depends on two other measurements, it is always interpreted together with the total and free PSA values and the overall clinical picture.
What to know about Percent Free PSA (% Free PSA)
Understanding Percent Free PSA (% Free PSA) means knowing what it reflects, what tends to move it, and the signs that suggest it’s worth a closer look — so you can bring the right questions to your next appointment.
This glossary entry is for informational purposes only and is not a substitute for professional medical advice. Read our Medical Disclaimer.
References
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Peer-reviewed research
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