PROSTATE SPECIFIC ANTIGEN, FREE (FREE PSA) - (P)
Test Code: FPSA
Test performed at: Health Sciences Centre
This test is indicated for measurement of free PSA in conjunction with total PSA to develop a ratio (% Free PSA) of fPSA to tPSA. This ratio is useful when used in conjunction with total PSA as an aid in distinguishing prostate cancer from benign prostatic conditions in patients that have a normal digital rectal examination and a total PSA value in the 4 to 10 ug/L range. Prostate biopsy is required for the diagnosis of prostate cancer.
Patient Preparation Instructions: Multivitamins (45–125 µg biotin) or biotin-only supplements up to 1 mg per day do not interfere with this test. Samples should not be taken from patients receiving therapy with high biotin doses (i.e. >5 mg/day) until at least 8 hours after the last dose.
Additional Information: The test method used is an Electrochemiluminescence (ECLIA) assay manufactured by Roche Diagnostics Inc. and performed on the Cobas Elecsys system.
Patient results determined by different assay manufacturers or methods are not comparable and cannot be used interchangeably for patient monitoring.
Plasma: 2.0 mL
Pediatric Plasma: 0.25 mL
Stability 5 days refrigerated, 3 months frozen
Serum: 2.0 mL
Samples must be transferred to an aliquot tube and stored frozen if analysis will not be complete within 48 hours (#110-10-05 Serum / Plasma Separation Procedure & Transport)
Free PSA: < 0.9 μg/L
Within 1 Day
This test is available to Urologists only