Home
HelpTest Code PSA-F PSA, Free & Total
Synonyms/Keywords
Prostate Specific Antigen, Free & Total
Specimen Requirements
| Fasting Required | Specimen Type | Preferred Container/Tube | Acceptable Container/Tube | Specimen Volume | Specimen Minimum Volume (allows for 1 repeat) |
Pediatric Minimum Volume (no repeat) |
|---|---|---|---|---|---|---|
| No | Serum | Serum Separator Tube (SST) | Red Top Tube (RTT) | 1.0 mL | 0.6 mL | 0.5 mL |
Collection/Processing Instructions
Remove serum from cells within 3 hours of centrifugation.
High doses of exogenous biotin (also termed Vitamin B7, Vitamin H or Coenzyme R) may interfere with this assay. It is recommended that patients refrain from consuming any multivitamin or supplement containing biotin for at least 72 hours prior to collection of a blood sample.
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated | 24 hours |
| Frozen | >24 hours to 5 months |
Rejection Criteria
Grossly hemolyzed
Test Components
Total Prostate Specific Antigen , Free Prostate Specific Antigen
Interferences
Human anti-mouse antibodies (HAMA) may be present in samples from patients who have received immunotherapy utilizing monoclonal antibodies.
High doses of exogenous biotin (also termed Vitamin B7, Vitamin H or Coenzyme R) may interfere with this assay.
Interpretations
Includes measurement of Total PSA and Free PSA by the Hybritech methods, and calculation of Percent Free PSA as follows: %Free PSA = 100 x (Free/Total). Percent Free PSA is indicated primarily with Total PSA results in the 3-10 ng/mL range. Generally %Free PSA levels of 20% or more suggest a higher probability of BPH whereas levels of 10% or less reflect a higher probability of prostatic carcinoma (see table below). This test requires ICD10 codes and waivers. Please refer to the Marshfield Clinic Lab Order Sheet for further information.
The following table indicates the Probability of Prostate Cancer for Total PSA's in the 4-10 range and various %Free PSA Levels for men with a non-suspect digital rectal exam: Probability of Prostate Cancer based on Age and %Free
PSA % FREE PSA 50-64 YEARS 65-75 YEARS
0.0 - 10.0% 56% 55%
10.1 - 15.0% 24% 35%
15.1 - 20.0% 17% 23%
20.1 - 25.0% 10% 20%
>25.0% 5% 9%
Reference Range Information
| Performing Location | Reference Range |
|---|---|
| Marshfield |
Total PSA: 0.0-4.0 ng/mL % Free PSA: = or > 25% |
Marshfield Labs Performing Department
Marshfield Labs Chemistry
Performing Information
| Performing Location | Day(s) Test Performed | Analytical Time | Methodology/Instrumentation |
|---|---|---|---|
| Marshfield | Monday through Friday | Less than 2 hours | Hybritch Ab Total and Free PSA/Beckman Coulter DXI |
CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 84154 | 1 | Free PSA |
|
|
| 84153 |
|
1 | Total PSA |
Outreach CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 84154 | 1 | Free PSA |
|
|
| 84153 |
|
1 | Total PSA |
Ordering Applications
| Ordering Application | Description |
|---|---|
| Cerner | Prostate Specific Antigen Free |