Prostate Cancer Screening – Why Some Cancers May Never Cause Harm

Understanding the Debate Around PSA Testing and Overdiagnosis

Prostate cancer is one of the most common cancers affecting men in the UK. Yet despite how common it is, routine nationwide prostate cancer screening remains controversial.

At OneMedicine, we believe patients deserve clear, balanced information to help them make informed decisions about their health. One of the biggest reasons prostate cancer screening is approached cautiously is because not all prostate cancers behave the same way.

Some cancers are aggressive and life-threatening. Others grow so slowly that they may never cause symptoms or shorten a person’s life.

Understanding that difference is central to the modern debate around PSA testing and prostate cancer screening.

Why Some Prostate Cancers Are Considered “Low Risk”

Many prostate cancers are biologically indolent. This means they grow extremely slowly and may remain confined to the prostate gland for decades.

In some men:

• Cancer cells divide very slowly
• The tumour remains small and localised
• The cancer never spreads beyond the prostate
• No symptoms ever develop

Research has shown that many older men have microscopic prostate cancer cells present without ever knowing about them. In these cases, the cancer existed but never became clinically important during life.

This is why doctors sometimes explain that certain prostate cancers may only become dangerous far beyond a normal lifespan. In practical terms, a person is far more likely to die from unrelated causes such as cardiovascular disease or stroke long before the prostate cancer becomes harmful.

The Difficulty With PSA Screening

The PSA blood test can help identify possible prostate abnormalities, but it is not a perfect test.

PSA stands for Prostate Specific Antigen, a protein produced by the prostate gland. Elevated PSA levels can occur for several reasons, including:

• Prostate cancer
• Benign prostate enlargement
• Prostatitis (inflammation)
• Urinary infection
• Recent ejaculation or exercise

The challenge is that PSA testing detects both aggressive cancers and harmless slow-growing cancers.

Current investigations such as MRI scans, biopsies, and Gleason scoring systems improve assessment, but they still cannot predict with complete certainty which cancers will become dangerous.

This creates a major dilemma in screening.

The Problem of Overdiagnosis

When large numbers of healthy men undergo PSA testing, some aggressive cancers are detected early and treated successfully.

However, many low-risk cancers are also found that may never have caused harm.

This is known as overdiagnosis.

Overdiagnosis matters because once cancer is identified, many patients understandably feel anxious about “living with cancer,” even if the risk is very low.

As a result, some men undergo treatments they may never have needed.

Why Overtreatment Can Be Harmful

Treatment for prostate cancer can sometimes lead to significant side effects, including:

• Erectile dysfunction
• Urinary incontinence
• Bowel symptoms
• Psychological stress
• Surgical complications

Although modern treatment techniques continue to improve, these risks remain important considerations when deciding whether treatment is appropriate.

For many low-risk cancers, active surveillance may be recommended instead of immediate surgery or radiotherapy.

Active surveillance involves careful monitoring with repeat PSA tests, MRI scans, and sometimes biopsies to watch for signs of progression.

Why the UK Does Not Offer Universal PSA Screening

Unlike some screening programmes, the UK does not currently offer routine PSA screening to all men.

This is because the overall balance of benefits and harms remains uncertain at a population level.

The concern is that widespread screening could:

• Detect large numbers of harmless cancers
• Lead to unnecessary biopsies and treatment
• Expose men to avoidable side effects

However, screening may be more beneficial in higher-risk groups, including:

• Men with a strong family history of prostate cancer
• Men of Black ethnicity
• Men with certain inherited genetic mutations such as BRCA2

These groups are more likely to develop aggressive prostate cancer.

A Simple Way to Understand the Issue

Doctors sometimes compare prostate cancers to two different types of fires.

One is a rapidly spreading wildfire – dangerous and urgent.

The other is a tiny ember that burns so slowly it may never spread or cause harm.

The difficulty is that screening often detects both, but medicine cannot always immediately tell which cancers will remain harmless and which will become dangerous.

That uncertainty is one of the main reasons prostate cancer screening remains such a carefully balanced issue.

Should You Have a PSA Test?

There is no single right answer for everyone.

The decision to have PSA testing should ideally involve an informed discussion about:

• Your age
• Family history
• Ethnicity
• Symptoms
• Personal preferences
• Potential benefits and limitations of testing

At OneMedicine, we offer private GP consultations where we can discuss prostate health concerns, PSA testing, urinary symptoms, and individual prostate cancer risk in a personalised and evidence-based way.

Book a Private GP Appointment

If you would like to discuss:

• PSA blood testing
• Urinary symptoms
• Family history of prostate cancer
• Prostate health concerns
• Men’s health screening

our clinicians at OneMedicine are here to help.

Early assessment and informed decision-making are key parts of modern prostate health care.

FAQs

Is PSA testing accurate?

PSA testing can be helpful, but it is not perfect. Elevated PSA levels do not always mean cancer is present, and some aggressive cancers may still occur with relatively normal PSA levels.

Can prostate cancer be harmless?

Some prostate cancers grow so slowly that they may never cause symptoms or affect lifespan. Others can be aggressive and life-threatening.

What is active surveillance?

Active surveillance means carefully monitoring low-risk prostate cancer rather than treating immediately. The aim is to avoid unnecessary treatment while still detecting progression early if it occurs.

Who is at higher risk of prostate cancer?

Higher-risk groups include men over 50, men with a family history of prostate cancer, Black men, and those with certain inherited genetic mutations.

Does OneMedicine offer PSA blood tests?

Yes. OneMedicine offers private GP consultations and PSA blood testing where clinically appropriate.