Includes Total PSA, Free PSA, % Free PSA (calculated)
Preferred Specimen(s) 2 mL serum
Instructions Non-frozen specimens must be received in the laboratory within 24 hours
Transport Container Plastic screw-cap vial
Transport Temperature
- Ambient 24 hrs,
- Refrigerated 24 hrs
Reject Criteria
- Gross hemolysis
- Gross lipemia
Methodology Chemiluminescence
Clinical Significance In men over age 50 years with total PSA between 4.0 and 10.0 ng/mL and those with prostate cancer tend to have lower % free PSA than those with benign prostatic hypertrophy (BPH), although there is considerable overlap in results for the two populations. % free PSA may aid in avoiding unnecessary biopsies in these circumstances.