Free
E-newsletter
Subscribe to Housecall
Our weekly general interest
e-newsletter keeps you up to date
on a wide variety of health topics.
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Results
By Mayo Clinic staffResults of PSA tests are reported as nanograms of PSA per milliliter of blood (ng/mL). There's no specific cutoff point between a normal and abnormal PSA level. Your doctor might recommend a prostate biopsy based on results of your PSA test and digital rectal exam, along with other factors.
Variations of the PSA test
Your doctor may use other ways of interpreting PSA results before making decisions about ordering a biopsy to test for cancerous tissue. These other methods are intended to improve the accuracy of the PSA test as a screening tool.
Researchers continue to investigate variations of the PSA test to determine whether they provide a measurable benefit. Variations of the PSA test include:
- PSA velocity. PSA velocity is the change in PSA levels over time. A rapid rise in PSA may indicate the presence of cancer or an aggressive form of cancer.
- Percentage of free PSA. PSA circulates in the blood in two forms — either attached to certain blood proteins or unattached (free). If you have a high PSA level but a low percentage of free PSA, it may be more likely that you have prostate cancer. This test is primarily used for men with a PSA level in the borderline range between 4 and 10. It is especially useful when determining the need for re-biopsy rather than in an initial screening state.
Talk to your doctor
Before getting a PSA test, talk to your doctor about the benefits and risks. If you decide that a PSA test is right for you, ask your doctor:
- When you will discuss the results
- What kinds of recommendations he or she might make if the results are positive
- How often you should repeat the test if the results are negative
Discussing these issues beforehand may make it easier for you to learn the results of your test and make appropriate decisions afterward.
-
Prostate cancer. American Cancer Society. http://www.cancer.org/cancer/prostatecancer/detailedguide/index. Accessed March 4, 2013.
- Prostate cancer screening. Centers for Disease Control and Prevention. http://www.cdc.gov/cancer/prostate/basic_info/screening.htm. Accessed March 4, 2013.
- Ilic D, et al. Screening for prostate cancer. Cochrane Database of Systematic Reviews. http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD004720.pub3/abstract. Accessed March 4, 2013.
- Moyer VA. Screening for prostate cancer: U.S. Preventive Services Task Force. Recommendation Statement. Annals of Internal Medicine. 2012;157:120.
- Prostate cancer screening (PDQ). National Cancer Institute. http://www.cancer.gov/cancertopics/pdq/screening/prostate/HealthProfessional/page1. Accessed March 4, 2013.
- PSA. Lab Tests Online. http://labtestsonline.org/understanding/analytes/psa/tab/test. Accessed March 4, 2013.
- Prostate-specific antigen (PSA) test. National Cancer Institute. http://www.cancer.gov/cancertopics/factsheet/detection/PSA. Accessed March 4, 2013.
- Hoffman RM. Screening for prostate cancer. http://www.uptodate.com/home. Accessed March 4, 2013.
- Castle EP (expert opinion). Mayo Clinic, Phoenix, AZ. April 17, 2013.
- Carter HB, et al. Early detection of prostate cancer: AUA guideline. American Urological Association. http://www.auanet.org/education/guidelines/prostate-cancer-detection.cfm. Accessed May 6, 2013.
Find Mayo Clinic on