Prostate Specific Antigen, Free Percentage (Includes Free PSA and Total PSA)
0080206
Ordering Recommendation
Do not use for initial prostate cancer screening; preferred test is total prostate specific antigen (PSA) (0070121) in conjunction with digital rectal exam (DRE). May be useful in distinguishing benign conditions from cancer in patients with mildly elevated total PSA and negative DRE.
Submit With Order
Mnemonic
PSA FP
Methodology
Quantitative Electrochemiluminescent Immunoassay
Performed
Sun-Sat
Reported
Within 24 hours
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
 
Collect
Serum separator tube or plasma separator tube. Also acceptable: Plain red, green (sodium or lithium heparin), lavender (EDTA), or pink (K2EDTA).  
Specimen Preparation
Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)  
Storage/Transport Temperature
Frozen.  
Unacceptable Conditions
Grossly hemolyzed specimens. Vaginal washings.  
Remarks
 
Stability
After separation from cells: Ambient: 8 hours; Refrigerated: 48 hours; Frozen: 3 months  
Reference Interval
By report
Results include: PSA-Free, PSA, PSA-Percent Free
Interpretive Data
The Roche PSA electrochemiluminescent immunoassay is used. Results obtained with different assay methods or kits cannot be used interchangeably. The Roche PSA method is approved for use as an aid in the detection of prostate cancer when used in conjunction with a digital rectal exam in men age 50 and older. The Roche Modular E170 PSA method is also indicated for the serial measurement of PSA to aid in the prognosis and management of prostate cancer patients. Elevated PSA concentrations can only suggest the presence of prostate cancer until biopsy is performed. PSA concentrations can also be elevated in benign prostatic hyperplasia or inflammatory conditions of the prostate. PSA is generally not elevated in healthy men or men with non-prostatic carcinoma.

ARUP uses the Roche Free PSA electrochemiluminescent immunoassay method in conjunction with the Roche PSA electrochemiluminescent immunoassay method to determine the free PSA percentage. The free PSA percentage is an aid in distinguishing prostate cancer from benign prostatic conditions in men age 50 and older with a total PSA between 3 and 10 ng/mL and negative digital rectal examination findings. Prostatic biopsy is required for the diagnosis of cancer. (Refer to: JAMA 1998; 279: 1542-1547)
In patients with total PSA concentrations of 4-​10 ng/mL, the probability of finding prostate cancer on needle biopsy by age in years is:
% Free PSA 50-​59 years 60-​69 years 70 years and older
0-​10% 49% 58% 65%
11-​18% 27% 34% 41%
19-​25% 18% 24% 30%
> 25 % 9% 12% 16%
Other factors may help determine the actual risk of prostate cancer in individual patients.
Note
The free percentage is calculated using the total and free PSA results.
CPT Code(s)
84153; 84154
Components
Component Test Code*Component Chart Name
0070121Prostate Specific Antigen, Total
0080207Prostate Specific Antigen, Free
0080209Prostate Specific Antigen, Percent Free
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Cross References
  • Free Prostate Specific Antigen
  • Free PSA
  • PSA Free/Total Ratio
  • PSA ratio
  • PSA Total and Free
  • PSA, Free
  • Total PSA