| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Prostate-Specific Antigen (PSA), Free
MessageTest Code
CPT Codes
84154
Preferred Specimen
Specimen Type: Serum
Collection Container: Serum gel
Specimen Volume: 3 mL
Minimum Volume
0.5 mL
Instructions
Additional Information: Serum for free PSA determinations should be drawn before performing prostatic manipulations.
Transport Container
Specimen Stability
Room temperature: Unacceptable
Refrigerated: 24 hours
Frozen: >24 hours
Avoid multiple freeze/thaw cycles
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Unlabeled, mislabeled, wrong tube type, hemolyzed, QNS, exceeds specimen stability requirements.
Methodology
Chemiluminescent microparticle immunoassay (CMIA)
Setup Schedule
Daily
Report Available
Same day
Limitations
The measurement of free PSA or the free/total PSA ratio is not an absolute test for malignancy.
The PSA values should be used in conjunction with information available from clinical evaluation and other diagnostic procedures such as DRE. Prostatic biopsy is required for the diagnosis of cancer.
DRE may cause clinically significant changes in the free PSA and free/total PSA ration in some patients. Prostatic massage, ultrasonography, cystoscopy, and needle biopsy may cause clinically significant elevation in free PSA levels.
Heterophilic antibodies in human serum can react with reagent immunoglobulins, interfering with in vitro immunoassay. Patients routinely exposed to animals or to animal serum products can be prone to this interference and anomalous values may be observed.
Reference Range
Performing Laboratory
Inova Laboratories
2832 Juniper Street
Fairfax, VA 22031
Last Updated: July 12, 2023
Last Review: N. Wolford, July 12, 2023