Free PSA (Free Prostate-Specific Antigen) Test

The Free PSA Test at Pamel Laboratories measures the amount of unbound (free) prostate-specific antigen in the blood. PSA exists in two main forms — free and bound — and analyzing the ratio of free PSA to total PSA helps differentiate between benign prostate conditions (like BPH) and prostate cancer, especially in men with borderline or moderately elevated total PSA levels.

This test is a valuable follow-up to a Total PSA Test, providing improved accuracy in prostate cancer risk assessment and helping reduce the need for unnecessary biopsies.

What the Test Measures:

• The concentration of free PSA (not bound to proteins) in the blood

• Often used with Total PSA to calculate the free-to-total PSA ratio (%)

Purpose of the Test:

• Assess the risk of prostate cancer in men with:

  • Moderately elevated total PSA (4–10 ng/mL)

  • No other clear symptoms

• Help distinguish between:

  • Benign prostate enlargement (BPH)

  • Prostate cancer

• Support decision-making regarding the need for prostate biopsy

Sample Type: Blood sample (serum)
Fasting Required: No
Turnaround Time: 1–2 working days

Interpretation Guide:

• Lower Free PSA (%): Higher likelihood of prostate cancer

• Higher Free PSA (%): More likely due to benign conditions

A free-to-total PSA ratio below 25% may warrant further investigation (e.g., biopsy)