New blood test to detect prostate cancer

Scientists at St George’s, University of London, are working on a blood test that uses DNA markers to identify prostate cancer cells that are shed into the bloodstream.

The researchers have demonstrated that by measuring the levels of these markers, not only can an accurate diagnosis of cancer be made, but the stage the cancer has reached — whether it is still localized or already has spread and become metastatic — can be identified.

In addition, certain markers, if switched on, will hopefully give information on how quickly the cancer will develop, and, therefore, when treatment must be introduced.

The current, most widely used method of detecting prostate cancer is the serum Prostate Specific Antigen (PSA) test, which is only 50 per cent accurate. Increased levels of PSA are elevated in non-malignant conditions, such as benign prostatic hyperplasia, prostatitis and even urinary tract infections. This new test, which is able to detect one prostate cancer cell among a sample of 100 million blood cells, is 95 per cent accurate.

Because of its inaccuracy, most elevated serum PSA results are followed up. This is done using a core needle biopsy. Samples of tissue are removed by inserting a needle through the wall of the rectum into the prostate gland. When pulled out, the needles remove a cylinder of tissue, usually about 1/2-inch long and 1/16-inch across. Up to 12 needles are normally used to ensure the prostate is thoroughly sampled.

After this invasive procedure, tissue samples are sent to a laboratory for analysis, often taking a week or so for results to be confirmed.

Owing to a high serum PSA, some men will invariably have a biopsy in which the result will been negative for prostate cancer. It is hoped that the new test, with its increased accuracy, will encourage men who suspect they have prostate problems to seek medical attention early on, enabling early treatment and leading, hopefully, to less men having prostate biopsies.

The research has been partly funded by Prostate Research Campaign UK. Brigadier John Anderson, Chief Executive of the charity says: “Many men fear seeking medical help, even when they suspect they have prostate problems, for fear that the diagnosis will involve painful and undignified tests. This simple, speedy, non-invasive test means patients need not fear traumatic tests to diagnose prostate cancer.And receiving an accurate diagnosis within days rather than weeks could mean they are treated more quickly and stand a greater chance of total recovery.”

The research has also been funded by the Everard and Mina Goodman Charitable Foundation.

The test is currently at the stage of validation, with further development regarding standardisation and formatting, and could be introduced on to the market next year.

Prostate cancer is increasingly recognised as a major health problem in the UK, being the most commonly diagnosed solid cancer and the most common cause of cancer-related deaths in men. Around 27,000 new cases are diagnosed in the UK each year and there are around 10,000 deaths from prostate cancer each year around the world.

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Notes to Editors

For any further information or to arrange interviews, contact Tamsin Starr, communications manager for St George’s, University of London, on 0208 725 1139;07786 982028 or email tstarr@sgul.ac.uk.

Prostate Research Campaign UK, 10 Northfields Prospect, Putney Bridge Road, London, SW18 1PE, visit www.prostate-research.org.uk or call 020 8877 5840.

St George’s, University of London is the only independently governed medical school in England and provides training to a wide range of healthcare students on one site. As well as providing courses in medicine and biomedical sciences, the Medical School also offers courses in midwifery, nursing, physiotherapy, radiography and social work in conjunction with Kingston University. The school is extremely active in research and has a high reputation in areas such as infection as well as diseases of the heart and circulation. Other areas of expertise include stroke rehabilitation, air pollution and addictions.