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Prostate Specific Antigen, Free

Item Value
Test Update Information Free PSA method changed fromSiemens Immulite 2000 to the Abbott Architect i2000 on March 25, 2013
Available Stat? No
Utilization Guidelines Although generally recommended for patients with Total PSA values between 4.0-10.0 µg/L the laboratory will accept requests for patients with Total PSA as low as 2.5 µg/L without approval.
Test code FPSA
Test group PSA
Performed by China Basin Chemistry
In House Availability Thursday (day shift)
Method Chemiluminescent Immunoassay (Abbott Architect i2000)
Container type Gold top
Amount to Collect 2 mL blood
Sample type Serum
Preferred volume 1 mL serum
Min. Volume 0.5 mL serum
Processing notes Freeze serum at -20C
Units %
Normal range See Additional Information
Synonyms Free PSA
Turn around times 1-8 days
Additional information Includes PSA, Total.

Medicare Local Medical Review Policy 9718, published in CA Medicare Bulletin 98-2 (February, 1998), applies.

Use of the test is based upon the claim of Catalona et al (JAMA 1995;274:1214) that when PSA levels are in the range of 4.1-10.0 µg/L, a higher proportion of free PSA identifies the patient with a relatively lower likelihood that a biopsy will show cancer.

In patients with Total PSA of 4-10 µg/L:

Free PSA Probability of Cancer
0-10% 56%
10-15% 28%
15-20% 20%
20-25% 16%
> 25% 8%
CPT coding 84153
LOINC code 12841-3
Last Updated 3/17/2017 9:07:29 AM
Entry Number 788
Lab Procedure Link Click here for Free PSA on Architect i2000 Procedure
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