SCREENING is a way of identifying healthy people in our community who may have an increased risk of developing a particular condition in the future such as cancer which affects more than one in three people in the UK during their lifetime.

The NHS offers a range of screening tests to different sections of the population.

Cancer screening can be effective at early-stage detection but only six per cent of cancers in the UK are screen-detected with programmes for cervical, bowel, breast and more recently targeted lung cancer screening.

However, despite these four recommended cancer screening tests, more than 70 per cent of cancer deaths are caused by cancers without recommended screening tests.

Routine single-cancer screening tests, such as mammography and colonoscopy, do save lives.

However, a patient undergoing single-cancer screening is more likely to be diagnosed with a different cancer than the one being screened for.

I’d like to reach out to our community and inform them of an exciting medical development that has the potential to revolutionise the efficiency of early cancer diagnosis in the foreseeable future.

With advances in medicine we have now entered a new era of screening for over 50 different types of cancer which can now be detected a lot earlier.

Detecting cancer early before it has had time to spread offers the best chance for successful treatment with the five-year survival rate four times higher compared to when cancer is diagnosed late.

Multi-Cancer Early Detection (MCED) tests are a simple blood test that looks for a signal shared by more than 50 different types of cancer.

This signal is often an extract of DNA released from very early stage cancer cells which is called circulating tumour derived DNA (ct-DNA).

ctDNA-based tests aim to detect a potential cancer signal and some tests also predict the likely site of origin of that cancer.

An example of an MCED test is the Galleri test which is the most developed at present and is currently being trialled in the NHS.

The Galleri test involves taking a single sample of blood and sending it to a laboratory.

The test screens for a signal shared by multiple cancers that would otherwise go unnoticed for many years.

If a cancer signal is detected, Galleri predicts the tissue type or organ associated with the cancer signal with up to 88 per cent accuracy to help guide follow-up diagnostic testing which may include scans and biopsies to confirm the diagnosis of cancer.

The Galleri test is designed for people aged over 50 years as age is the biggest risk factor for cancer.

Adults aged over 50 years are 13 times more likely to have cancer compared to people under the age of 50.

Cancer risk increases for everyone as they age regardless of family history.

Indeed, only a small proportion of cancers approximating to five to 10 per cent are due to genetic factors and inherited.

The NHS-Galleri trial is looking into the use of the Galleri blood test to see if it can help the NHS to detect cancer early when it is usually a lot easier to treat.

Over 140,000 volunteers aged 50 to 77 have registered to take part in the trial after receiving an invitation letter from the NHS.

The NHS-Galleri trial is not accepting new participants at this time as registration is closed.

NHS England has decided that it will wait to see the final results of the trial, which is expected to be announced in 2026, before considering whether an NHS rollout of the Galleri multi cancer early detection test should go ahead.

Our columnist Dr Jason Seewoodhary is a former Worcester GP.