Prostate-Specific Antigen (PSA) Ultrasensitive, Serum
Use
The Prostate-Specific Antigen (PSA) Ultrasensitive test is useful for detecting prostate cancer when used alongside a digital rectal examination in men aged 50 years and older. It is also crucial for assessing prognosis and management in individuals diagnosed with prostate cancer and for monitoring disease post-radical prostatectomy. This test offers ultrasensitive measurements of PSA levels to potentially identify early biochemical recurrence (BCR) and aid in the selection of secondary therapies, despite the ongoing debate about its clinical utility at such low thresholds.
Special Instructions
Free PSA can be added to this test within 72 hours if the specimen has been shipped frozen. Both free and total PSA results require ordering a combined test. Provide the patient's age when submitting the test.
Limitations
The test should not be used for initial prostate cancer screening purposes. PSA levels may be affected by procedures such as cystoscopy, prostate biopsy, or urethral instrumentation. Immunological interference can occur due to antibodies like human anti-mouse antibodies (HAMA) or antibodies against components like streptavidin or ruthenium. There is no high-dose hook effect up to certain concentrations, and biotin interference is minimal.
FDA ApprovedNew York Approved
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 35741-8
- 35741-8
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.75 mL
Container
Plastic vial
Collection Instructions
Within 2 hours of collection, centrifuge the specimen. For red-top tubes, aliquot serum into a plastic vial.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 14 days |
| Frozen | 180 days |