Scientists have tested a new blood test that could help doctors in the future detect when prostate cancer treatments are starting to fail.

The breakthrough could lead to more personalised treatments for patients and even extend the lives of men with advanced disease, according to a new study.

The study, by University College London, tested whether tiny particles of tumour DNA in the blood could track the cancer’s continued growth.

The study, conducted at 14 different NHS centres in the UK, involved 117 men who had recently been diagnosed with advanced prostate cancer.

The researchers found that three in 10 patients still had detectable tumour DNA in their blood six to 12 weeks after starting treatment.

Most importantly, when these DNA tests were combined with PSA levels, they identified men who had a 20-fold higher risk of death than those who had no tumour DNA in their blood and also had low PSA levels.