When it comes to detecting cancer, the words screening and diagnosis are often used interchangeably. But they mean very different things - and understanding the difference could make a real impact on your health.

Screening: Taking a proactive step

Cancer screening is for people without symptoms. It’s a proactive way to look for early signs of cancer or changes that could become cancer in the future.

At Check4Cancer, we offer evidence-based screening services for six common cancers - breast, cervical, bowel, lung, prostate and skin - to help people take control of their health and act early, in case there is something of concern that doesn’t yet have any symptoms.

Each screening has a clear purpose:

• Breast screening detects cancers too small to feel.
• Cervical screening finds abnormal cells before they turn cancerous.
• Bowel screening checks for hidden traces of blood or early signs of disease.
• Lung screening (low-dose CT scan) looks for subtle early changes, especially in people with a smoking history.
• Prostate screening helps men understand their risk and detect disease early.
• Skin screening examines every mole or lesion to spot changes that could indicate skin cancer.

Screening offers peace of mind - and when something is found early, treatment is often simpler, faster and more effective.

Karen hadn't noticed any symptoms, but a screen detected something unexpected.

Read her story

Diagnosis: Acting quickly when symptoms appear

Diagnostic testing is different. It’s for people who already have symptoms or a concern that needs investigating - for example, a lump, bleeding, a mole that’s changed, or a persistent cough.

A diagnostic test aims to confirm or rule out cancer as quickly as possible.

At Check4Cancer, we provide fast, consultant-led diagnostic pathways for breast, skin [and bowel cancer], giving people quick access to expert assessment, imaging and results.

Knowing whether you need a screening or a diagnostic test is essential - it ensures you get the right help at the right time.

When to screen and when to act

• Book a screening if you feel well and want reassurance or to check for early signs of cancer.
• Seek diagnostic testing if you have any new or persistent symptoms, such as a lump, bleeding, unexplained weight loss, or a mole that’s changed.
• Don’t wait. Whether through a screening or diagnostic test, getting checked early offers the best chance of successful treatment.

Because when it comes to cancer, it’s always better to know.