Prostate-specific Antigen (PSA) Free:Total Ratio Blood Test
The Prostate-specific Antigen (PSA) Free:Total Ratio Blood Test compares Total PSA (the amount that is bound to blood proteins) to Free PSA (floats unbound in the blood).
Description
The Prostate Specific Antigen (PSA) Free:Total Ratio provides several measurements which help to screen for prostate cancer. PSA is a protein produced by the prostate gland. Elevated PSA levels may indicate a higher likelihood of having prostate cancer. However, not all cases of prostate cancer will cause elevated PSA levels and there are conditions other than cancer which may cause elevated PSA.
Free PSA is the portion of PSA which is not bound to other proteins in the blood. Generally, men with lower levels of Free PSA have a higher likelihood of having Prostate Cancer. Free PSA measurements are useful for people with borderline or moderately increased total PSA levels.
The test is used to help determine the need for:
- Biopsy of the prostate
- Detect prostate cancer recurring
- Monitor treatment for prostate cancer