Prostatic Specific Antigen, Diagnostic

PSAD

PSA Diagnostic

Serum GOLD (SST)

Serum is the recommended sample. Plasma samples should not be used. Specimens should be collected in such a way as to avoid hemolysis. The specimen should be allowed to clot fully and the serum separated by centrifugation.

Stability/Storage

1. If the serum sample is to be assayed within 24 hours after collection, the specimen should be stored in a refrigerator at 2 to 8°C.
2. Specimens held for longer times (up to 5 months) should be frozen at -20°C or colder.
3. Specimens to be held for longer than 5 months should be frozen at -70°C.
4. Repeated freeze-thaw cycles have no effect on free PSA, total PSA, or percent free PSA. However, prompt refreezing of the thawed samples is recommended.

0.0-3.99 ng/mL

NOTE: The concentration of PSA in a given specimen determined with assays from different manufacturers can vary due to differences in assay methods and reagent specificity. The results reported by the laboratory to the physician must include the identity of the PSA assay used. Values obtained with different assay methods cannot be used interchangeably.
 

Prostate cancer is the most common type of cancer found in men in the United States, with an incidence of approximately one case for every ten men. It is also the second leading cause of cancer deaths among American men. A reliable test for detecting early stage prostate cancer, when the tumor is confined to the gland and effective treatment can be provided, can be of great value to the physician. Historically, a majority of prostate cancers had advanced beyond the gland at the time of diagnosis. The digital rectal examination (DRE) is a commonly used technique for prostate cancer detection; nevertheless DRE, as it is generally performed in medical practice, misses a significant number of cancers, including many organ-confined tumors.