Prostate-specific Antigen (PSA), Free:Total Ratio Reflex

Casandra

Casandra Test Code LC71550Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 480772CPT Code 84153

Prostate-specific Antigen (PSA), Free:Total Ratio Reflex

Also known as: PSA Total:Free Ratio Reflex

Clinical Use

Order Test

Use

Measure the percentage of free (uncomplexed) PSA relative to the total amount of PSA in men with serum PSA concentrations between 4.0 and 10.0 ng/mL.

Special Instructions

Specimens should not be drawn immediately after digital rectal examination (DRE), prostatic massage, or transrectal ultrasound (TRUS). PSA sampling should not be performed for at least six weeks after prostatic biopsy. It is recommended to use only one assay method consistently to monitor each patient's course of therapy. This procedure does not provide serial monitoring and is intended for one-time use only. If serial monitoring is required, order the serial monitoring number 480640.

Limitations

The interpretive guidelines for percent free PSA are based on a population of men with normal digital rectal exam (DRE) and total PSA between 4.0 and 10.0 ng/mL. These guidelines should not be applied to other populations. Patients taking finasteride may experience diminished levels of PSA, and the serum levels of both total and free PSA increase with prostate manipulation but free PSA levels return to normal quicker. The use of percent free PSA has no specific recommendations for populations other than those with normal DRE and PSA between 4.0 and 10.0 ng/mL.

Test Details