PSA
Also called Prostate-specific antigen
PSA (prostate-specific antigen) is a protein made by both normal and cancerous cells of the prostate, the gland below the bladder that makes the fluid part of semen. A PSA blood test measures how much is circulating.
A raised PSA does not mean cancer on its own. An enlarged prostate (benign prostatic hyperplasia), prostatitis, urinary tract infections and some medicines can all raise it, and the test cannot show which cause is responsible, so a high result leads to further tests rather than a diagnosis. Because of the balance of benefits and harms, major organizations now advise that men discuss PSA screening with a clinician before deciding.
Why it matters after 45
PSA levels tend to rise with age and the risk of prostate cancer increases after 50, and PSA is also part of safety monitoring around testosterone therapy. The American Urological Association says PSA should be measured in men over 40 before testosterone therapy starts, to exclude an existing prostate cancer. The Endocrine Society recommends against starting therapy without further urological evaluation when PSA is raised, and calls for a urology referral if PSA rises in a confirmed way during the first year of treatment, with monitoring after that following standard screening guidance.
Where it comes up
References
- MedlinePlus. Prostate-Specific Antigen (PSA) Test. U.S. National Library of Medicine. https://medlineplus.gov/lab-tests/prostate-specific-antigen-psa-test/
- National Cancer Institute. Prostate-Specific Antigen (PSA) Test. https://www.cancer.gov/types/prostate/psa-fact-sheet
- American Urological Association. Evaluation and Management of Testosterone Deficiency (AUA Guideline). https://www.auanet.org/guidelines-and-quality/guidelines/testosterone-deficiency-guideline
- Endocrine Society. Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline, 2018. https://www.endocrine.org/clinical-practice-guidelines/testosterone-therapy
Definitions here are educational and are not medical advice. They explain what a term means; the pages linked above cover what it means for you, and a clinician reviews your own results. Editorial & medical review policy · All glossary terms