New prostate cancer test

A far more effective blood test for prostate cancer is being developed by scientists.

They have discovered a chemical marker produced by cancerous tissue which reveals whether a man has the disease and how severe it is.

The current blood test measures the levels of a protein, PSA, made by the prostate.

However, its unreliability means that older men are not routinely screened for the disease. False positive and false negative results mean it is wrong more often that it is right and positive results can lead to unnecessary operations.

The new test looks at levels of prostasomes, the minuscule sacs of liquid produced by prostate cells.

The researchers found that levels were higher in 20 patients with prostate cancer than a similar sample of 20 men without the disease.

Prostate cancer

They think the test could also apply to other types of tumours.

Dr Masood Kamali-Moghaddam, from Uppsala University, Sweden, said: ‘In the limited patient material examined in our study, blood levels of prostasomes seem to correlate more closely with the severity of the disease than do PSA levels.’

The test is reported in the journal Proceedings of the National Academy of Sciences.

The Prostate Cancer Charity welcomed the study, but stressed it was still at the earliest stages with a usable version still many years away.

Spokesman Dr Helen Rippon said: ‘This study is an interesting development in helping to meet one of the biggest challenges facing prostate cancer research – finding a test which can reliably diagnose the most aggressive form of the disease.

‘However, there is a long road ahead for this line of research. The technology – looking at levels of prostasomes, small bubbles of fluid released by prostate cells – is very complicated and would need to be refined before it could find its place into clinical practice with men.

‘The usefulness of this technology will also need to be tested on much larger groups of men, to see exactly how well it performs in detecting prostate tumours.

‘However, it is encouraging to see scientists taking such an original approach to developing a new test for prostate cancer. It is through pioneering research such as this that we will be able to finally develop a more reliable test for men.’

Around 36,000 men are diagnosed with prostate cancer each year in Britain. Although the disease can be fatal – killing more than 10,000 people – many cancers grow so slowly they never need treatment.