PSA (prostate‑specific antigen) tests measure the amount of PSA, a protein produced by prostate cells, in the blood. The test gives a numerical value representing PSA concentration; higher values mean more PSA is circulating.

Elevated PSA can indicate prostate cancer, but it is not specific: benign prostate enlargement, inflammation/infection (prostatitis), recent ejaculation or prostate manipulation can also raise PSA, and some cancers produce only small PSA changes. Clinicians use PSA level trends, age, physical exam findings and other measures (e.g., free‑to‑total PSA, imaging or biopsy) to assess cancer risk and guide further testing rather than relying on a single PSA value alone.

A PSA sample is collected from a blood sample — typically a small venous draw from a vein in the arm performed by a phlebotomist or clinician and sent to a laboratory for measurement. Some at‑home or mail‑in options use a finger‑stick (capillary) blood sample; in all cases the tube or card is labeled and processed by a lab to determine the PSA concentration.

You may be asked to avoid recent ejaculation, vigorous exercise, or prostate manipulation (like a digital rectal exam or biopsy) for 24–48 hours before the test because these can temporarily raise PSA. PSA testing helps you and your clinician monitor or screen PSA levels but is not a definitive cancer diagnosis—abnormal results require clinical follow‑up and interpretation by a healthcare professional.

Your PSA (prostate‑specific antigen) result measures the amount of a protein made by prostate tissue in your blood; higher values, or a steady rise over time, are associated with a greater chance that abnormal prostate cells — including prostate cancer — may be present. A low or stable PSA generally means lower short‑term risk, while a higher or rapidly increasing PSA raises concern and usually prompts further evaluation.

PSA is not cancer‑specific: benign conditions (enlarged prostate, inflammation/infection, recent sexual activity, certain procedures or medications) and age can change PSA levels, and a normal PSA does not completely rule out cancer. Clinicians interpret your PSA alongside your age, prostate size, symptoms, and previous PSA trends and may use repeat testing, percent free PSA, imaging, or biopsy to clarify risk. These results help you and your clinician decide next steps but are not by themselves a definitive diagnosis of cancer.

PSA is a useful blood marker but an imperfect indicator of prostate cancer: raised PSA can be caused by benign prostate enlargement, prostatitis, recent ejaculation or procedures, and some medications, so many men with elevated PSA do not have cancer (false positives); conversely, some prostate cancers produce little or no PSA, so a “normal” value does not guarantee absence of cancer (false negatives). Because of these limitations, PSA alone cannot diagnose or rule out prostate cancer.

Clinicians interpret PSA together with age-adjusted ranges, serial trends (velocity), physical exam findings, imaging (such as MRI) and, when indicated, targeted biopsy. Screening can detect cancers earlier but also leads to overdiagnosis and overtreatment; the best approach depends on individual risk factors and preferences, so PSA results are most reliable when integrated into a broader clinical assessment.

How often you should test PSA depends on your age, baseline PSA, family history and other risk factors rather than a one‑size‑fits‑all interval. For average‑risk men in middle age many clinicians offer testing roughly every 1–4 years (every 2 years is a common compromise). If your baseline PSA is low (for example <1 ng/mL) testing can often be spaced to every 2–4 years; if it is in an intermediate range (about 1–3 ng/mL) testing every 1–2 years is frequently recommended; if the PSA is higher or shows any rise on repeat testing, sooner repeat testing and urology evaluation are warranted.

Men at higher risk (African ancestry, strong family history, or other risk factors) are usually offered earlier and more frequent testing (often starting in the 40s or mid‑40s). Screening is generally individualized with shared decision‑making and is often stopped when life expectancy is limited (commonly cited around 10–15 years) or at older ages; always follow up abnormal results with your clinician for repeat testing and appropriate referral.

No — PSA test results are not diagnostic. They highlight patterns of imbalance or resilience in prostate biology: a single elevated or changing PSA can raise concern but does not by itself confirm cancer.

PSA results must be interpreted by a qualified clinician alongside symptoms, medical history, and other laboratory or biomarker data; clinicians often use repeat measurements and additional tests to determine whether further evaluation is needed.

PSA can rise for many noncancer reasons (prostatitis/UTI, recent ejaculation, prostate manipulation, cycling/straddle activity, and benign prostatic enlargement), so first steps are to avoid ejaculation and vigorous cycling/straddle activities for 24–48 hours before repeat testing, tell your clinician about recent procedures or infections, and treat any diagnosed prostatitis or urinary infection — antibiotics may lower PSA if infection is present. If you take medications that affect PSA (for example 5‑alpha‑reductase inhibitors such as finasteride or dutasteride), discuss with your doctor because these drugs lower PSA and change how results are interpreted rather than reliably “improving” cancer risk.

Longer term, maintain a healthy weight, regular exercise, a balanced diet, and stop smoking (all general health measures that may influence prostate health), but there is no guaranteed way to lower PSA that ensures lower cancer risk. The best course after an abnormal result is follow-up with your clinician or urologist for repeat testing, possible urine tests, imaging or referral for further evaluation — and to make decisions about treatment or surveillance based on the full clinical picture rather than PSA alone.