Prostate cancer blood test that 'reads genetic changes like a barcode' trialled successfully

Scientists have developed a 'barcode' blood test that reads genetic changes to pick out the most aggressive prostate cancers.

'We've shown it is possible to learn more about prostate cancers by the signs they leave in the blood, allowing us to develop a test that is potentially more accurate than those available now and easier for patients than taking a biopsy', said Professor Johann de Bono, who led the study at the Institute of Cancer Research, UK.

The test works by reading the pattern of genes switched on and off in blood cells as a result of the disease. 'Our test reads the pattern of genetic activity like a barcode, picking up signs that a patient is likely to have a more aggressive cancer. Doctors should then be able to adjust the treatment they give accordingly', said Professor de Bono.

Researchers scanned all the genes present in blood samples from 100 patients with either advanced or low-risk, early-stage prostate cancer. The patients were divided into four groups based on their pattern of gene activity, as measured by RNA levels. Patients in one of the four groups showed a significantly lower survival rate after two and a half years when compared to the others. These patients had genetic 'barcodes' that shared activity in nine specific genes.

Some of the nine genes were involved in the immune system, leading scientists to speculate that patients with this genetic profile had defects in their immune systems that allowed the cancer to spread more aggressively.

Using these nine genes, researchers were able to identify patients who had the worst survival rates in a separate group of 70 patients with advanced cancer. Those without the genetic pattern survived more than twice as long as those with the genetic pattern.

Similar findings were also published by US researchers, led by Professor William Oh at the Tisch Cancer Institute at the Mount Sinai Medical Center, USA. This blood test used six genes to identify patients with more aggressive prostate cancer.

'For years it has been extremely difficult to try to predict which men have very aggressive tumours and which do not', said Dr Kate Holmes, head of research at Prostate Cancer UK that part-funded the study, to the Mail Online.

Dr Holmes added: 'If these early findings can be confirmed by much larger studies over time this method could potentially be used to help inform how aggressive a tumour will be and empower men and their clinicians to make much more informed decisions about which treatments are best for their individual circumstances'.

The studies were published in the journal Lancet Oncology.