PSA, Total with Reflex to PSA, Free
This test measures total PSA (prostate specific antigen) in a blood sample. Quest describes PSA as a useful addition to the digital rectal exam in early detection of prostate cancer, and in certain cases the lab automatically also measures the percentage of Free PSA.
About this test
PSA is measured using an immunoassay on a frozen serum sample. When Total PSA falls within a range Quest specifies for a certain age group, the lab reflexes to a Free PSA measurement, which Quest describes as an estimate of the probability of cancer that can help avoid unnecessary biopsies.
Quest notes that PSA levels can be elevated in both benign and malignant prostate conditions, and that the test is also used to help follow people with a history of prostate cancer — levels fall toward undetectable after complete tumor removal and may rise again if disease returns or persists.
Who might consider this test?
- Often looking at prostate health as part of a broader evaluation
- Sometimes alongside a digital rectal exam
- Are already being followed for a history of prostate cancer and want a marker to track over time
Test details
| Quest code | 17569 |
|---|---|
| Methodology | Immunoassay |
| Sample type | 2 mL frozen serum |
| Collection | Quest patient service center |
Related tests and panels
Quest resources
Additional details
What this test looks at
The test reports Total PSA from a frozen serum sample, measured using immunoassay methodology. Quest lists a reflex rule: for men in a certain age group whose Total PSA falls in a specified range, the lab automatically also measures percent Free PSA.
How it's often used alongside other tests
Quest describes PSA as a useful addition to the digital rectal exam in early detection of prostate cancer, and the Free PSA reflex as help in avoiding unnecessary biopsies when the initial result is in that range. A clinician reads the PSA value together with exam findings and, when it applies, the Free PSA percentage.
This test isn't orderable through the store yet. Requesting it tells us you want it and puts you on the list to be told when that changes — there is no charge and no commitment, and requesting does not place an order.
Laboratory results should always be interpreted by a licensed clinician who knows your health history. This page is information about a test, not medical advice.
Frequently asked questions
What does this test measure?
It measures total PSA in serum, with an automatic reflex to percent Free PSA in men in a certain age group whose Total PSA falls in a range Quest specifies.
How is the sample collected?
The test uses a frozen serum sample from a routine blood draw.
Do I need to prepare for this test?
No preparation instructions are listed for this test, though people follow any instructions their ordering clinician provides.
What is the Free PSA reflex?
For men in a certain age group whose Total PSA falls in a range Quest specifies, the lab automatically also measures percent Free PSA, which Quest describes as an estimate of the probability of cancer that may help avoid unnecessary biopsies.
Is PSA only useful before a prostate cancer finding?
No. Quest notes that PSA decreases to undetectable levels after complete tumor removal and may rise again if disease returns or persists, which is why it is also used to help follow people with a history of prostate cancer.