PSA (Prostate-Specific Antigen)

What is PSA?

Prostate-specific antigen (PSA) is a protein produced by cells in the prostate gland — both normal cells and cancerous ones. Its physiological role is to liquefy semen after ejaculation. Normally, very little PSA enters the bloodstream, but when the prostate is enlarged, inflamed, or affected by cancer, PSA leaks more readily into the circulation, raising the measured blood level.

PSA testing was introduced in the late 1980s and has become the most widely used tool for prostate cancer screening and monitoring. However, it is important to understand that PSA is prostate-specific, not cancer-specific. Many conditions other than cancer can raise PSA, which is why a raised result always requires clinical interpretation and further investigation rather than immediate panic.

PSA levels naturally increase with age as the prostate gland enlarges over time. This is why age-specific thresholds are more clinically meaningful than a single universal cutoff. For men in their forties, a PSA above 2.5 ng/mL may warrant investigation, whereas for a man in his 70s, a result of 5–6 ng/mL may be attributable to benign growth rather than malignancy.

In men already diagnosed with prostate cancer, PSA is an invaluable monitoring tool. After radical prostatectomy, PSA should become undetectable; any subsequent rise (biochemical recurrence) signals possible residual or returning disease and prompts further investigation and treatment decisions.

Normal reference range

• General threshold (all ages): below 4.0 ng/mL
• Men aged 40–50: below 2.5 ng/mL is more appropriate
• Note: PSA rises naturally with age and prostate size — interpretation is always age- and context-specific

Important: Reference ranges vary between laboratories and depend on individual factors including age, sex, pregnancy status, and medication. Always interpret your result in the context of a clinician review. The Vesey reviews every result before release.

What a high PSA may indicate

A PSA above the age-appropriate threshold warrants further clinical assessment. Important causes of elevated PSA include:

• Prostate cancer — the most serious cause; higher PSA levels, rapid PSA rise over time (PSA velocity), and a low PSA density (PSA relative to prostate volume) all increase the likelihood of cancer
• Benign prostatic hyperplasia (BPH) — non-cancerous prostate enlargement is the most common cause of elevated PSA in older men; a large prostate simply produces more PSA
• Prostatitis — bacterial or non-bacterial prostate inflammation can cause dramatic PSA elevation, sometimes above 100 ng/mL in acute bacterial prostatitis
• Recent ejaculation — transiently raises PSA; avoid ejaculation for 48 hours before the test
• Urinary tract infection — infection involving the prostate elevates PSA
• Prostate instrumentation — catheterisation, cystoscopy, or prostate biopsy cause marked PSA elevations for up to 4–6 weeks
• Vigorous cycling or horse riding — perineal trauma can transiently raise PSA

Who should consider PSA testing?

PSA testing is not currently part of a national screening programme in England (unlike in some other countries), but men can request it through their GP or privately. The following groups particularly benefit from knowing their PSA:

• Men aged 50 and over with urinary symptoms (difficulty starting urination, poor stream, frequency, nocturia)
• Men with a first-degree relative (father or brother) diagnosed with prostate cancer, particularly before age 65
• Men of Black African or Caribbean heritage, who have a 1-in-4 lifetime risk of prostate cancer (versus approximately 1-in-8 in the general population) and may benefit from earlier screening from age 45
• Men who wish to establish a baseline for serial monitoring

Get tested at The Vesey, Sutton Coldfield

PSA is measured within the following panel at The Vesey Private Hospital:

• Prostate Profile — £145 (PSA with clinician review and age-specific interpretation)

Results are reviewed by a clinician before secure release, typically within 24 hours. Please avoid ejaculation for 48 hours before your appointment. Appointments available Monday–Saturday.

Frequently asked questions

What is a normal PSA level?

A PSA below 4 ng/mL is the traditional general threshold. For men aged 40–50, below 2.5 ng/mL is more appropriate. PSA naturally rises with age and prostate size, so interpretation is always age- and context-specific. A single result is rarely definitive — trend over time often matters more.

Does a raised PSA always mean prostate cancer?

No. Most men with a raised PSA do not have prostate cancer. Common causes include benign prostatic hyperplasia, prostatitis, recent ejaculation, vigorous cycling, and UTI. A raised PSA triggers further investigation — not diagnosis — and must always be interpreted alongside clinical history and examination.

Who should consider a PSA test?

Men aged 50 and over, particularly those with urinary symptoms or a family history of prostate cancer. Men of Black African or Caribbean heritage benefit from screening from age 45 due to higher lifetime risk. Men with a first-degree relative diagnosed before age 65 are also at higher risk.

What should I avoid before a PSA test?

Avoid ejaculation for 48 hours before the test. Also avoid vigorous cycling or perineal trauma for 48 hours. Do not have the test during or immediately after a UTI or prostatitis episode — wait until treatment is complete. Inform your clinician of any recent prostate procedures or catheterisation.

What happens if my PSA is raised?

A raised PSA typically leads to a repeat measurement after excluding transient causes, followed by a clinical prostate examination. If concerns remain, a referral for mpMRI (multiparametric MRI) of the prostate and possible targeted biopsy follows the current NHS pathway. Our clinicians can advise on next steps and appropriate onward referral.