Quick Facts
- Sample: Blood
- Fasting: No fasting required. Avoid ejaculation and strenuous exercise for 72 hours before testing, stop biotin at least 72 hours prior, and wait at least six weeks after a prostatic biopsy.
- Turnaround: 2-3 business days. May take longer based on weather, holiday, or lab delays.
What This Test Measures
This test measures both Total PSA and Free PSA in your blood, then calculates the % Free PSA ratio. PSA is a protein produced by the prostate gland. Total PSA reflects overall PSA levels, while Free PSA is the portion of PSA that is not bound to other proteins in the blood. The % Free PSA is a calculated value derived from these two direct measurements, rather than a value measured on its own.
This test helps screen for prostate cancer and helps determine the need for a prostate biopsy. It can also help detect prostate cancer that has recurred and help monitor treatment for prostate cancer. Free PSA measurements are particularly useful for people with borderline or moderately increased Total PSA levels, since men with lower Free PSA levels generally have a higher likelihood of having prostate cancer.
Benefits
- Measures Total PSA and Free PSA from a single blood draw
- Calculates the % Free PSA ratio to add context to PSA results
- Helps determine whether a prostate biopsy may be needed
- Supports detection of prostate cancer recurrence
- Helps monitor prostate cancer treatment over time
- Provides added insight for borderline or moderately elevated PSA
Who Is This Test For?
- People whose provider wants to screen for prostate cancer
- People with borderline or moderately elevated Total PSA results
- People whose provider is evaluating the need for a prostate biopsy
- People being monitored for prostate cancer recurrence
- People currently undergoing treatment for prostate cancer
How It Works
- Order Your Test Online
- Visit a Local Lab
- Get Results Online
FAQ
1. What is the purpose of this test?
This test measures Total PSA and Free PSA in your blood and calculates the % Free PSA ratio to help evaluate prostate health. It helps screen for prostate cancer, helps determine the need for a prostate biopsy, helps detect prostate cancer recurrence, and helps monitor treatment for prostate cancer. Elevated PSA may indicate a higher likelihood of prostate cancer, but not all prostate cancer causes elevated PSA, and other conditions can also raise PSA. This test does not diagnose cancer on its own, and a normal result does not rule out cancer.
2. Who should consider this test, and when?
This test may be appropriate for people whose healthcare provider wants to screen for prostate cancer, people with borderline or moderately elevated Total PSA who need more context, people whose provider is deciding whether a biopsy is needed, and people being monitored for prostate cancer recurrence or currently in treatment for prostate cancer. It does not replace a full clinical evaluation, and one result does not provide a complete assessment on its own. Your provider can help determine whether and when this test fits your specific situation.
3. How does this test differ from other cancer-related tests?
This test specifically measures Total PSA and Free PSA from blood and calculates the % Free PSA ratio, which is a derived value rather than a direct measurement. Its supported roles are limited to screening, supporting the decision for a prostate biopsy, detecting recurrence, and monitoring treatment. Not all cancer-related laboratory tests serve the same purpose or measure the same analytes, and this test's scope is limited to what is described here.
4. Do I need to fast or prepare before this test?
No fasting is required for this test. Avoid ejaculation and strenuous exercise for 72 hours before testing, and stop biotin consumption at least 72 hours before the sample is collected. PSA sampling should not be performed for at least six weeks after a prostate biopsy.
5. How quickly will I get results?
Results are typically available in 2-3 business days. Results may take longer based on weather, holidays, or lab delays.
6. How do I interpret my results?
Interpreting your results depends on your Total PSA, Free PSA, the calculated % Free PSA ratio, your medical history, and other clinical findings. An elevated or abnormal result does not automatically confirm that prostate cancer is present, since conditions other than cancer can also raise PSA levels. A normal result does not automatically rule out prostate cancer. Your provider may review these results alongside other laboratory findings, imaging, or clinical evaluation. If this test is used for monitoring, tracking results over time may provide useful context, though changes do not guarantee a specific clinical conclusion.
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
7. What should I do if my results are abnormal?
Review abnormal results with a qualified healthcare provider, who may consider additional evaluation based on your results, history, and clinical presentation. An abnormal result does not by itself mean prostate cancer is present. Do not stop prescribed medication unless instructed by your healthcare provider.
8. How often should I get tested?
How often you are tested should be determined by your healthcare provider, based on your individual situation and the reason this test was ordered — whether that is screening, biopsy decision support, recurrence detection, or treatment monitoring. Follow your provider's guidance for retesting rather than a fixed schedule.
Pre-test preparation
No fasting is required. Avoid ejaculation and strenuous exercise for 72 hours before testing. The patient should stop biotin consumption at least 72 hours prior to the collection. PSA sampling should not be performed for at least six weeks after prostatic biopsy.
Do not stop prescribed medication unless instructed by your healthcare provider.
