Free PSA
Hormone markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Free PSA values sit together on one chart and you walk into your next appointment prepared.
What is Free PSA?
The portion of PSA in the blood that is not bound to other proteins, measured as a follow-up when total PSA is elevated.
PSA circulates in two forms, bound to proteins and unbound (free); free PSA measures just the unbound part. It is usually a follow-up test in men whose total PSA is elevated, used to help decide whether a prostate biopsy is worthwhile. On its own the free PSA number means little; it is meaningful mainly as part of the free-to-total ratio (percent-free PSA). Like total PSA, it applies only to men and does not diagnose cancer by itself.
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References
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