Identifying which men with advanced prostate cancer will benefit from targeted treatments could be made easier with a quick and cost-effective test, researchers have found.

The test looks for genomic errors in cancer cells that impede their ability to repair broken DNA – and make them sensitive to some specialised drugs. The research, which was published in the journal Clinical Cancer Research, was led by scientists from the Cancer Biomarkers laboratory team at The Institute of Cancer Research, London.

Genomic sequencing is increasingly used to match cancer patients to clinical trials of targeted drugs that are most likely to work, based on the particular genetic characteristics of each tumour.

Currently, this assessment is usually done using more expensive systems that sequence the entire genome – but the test used by this research team uses a gene panel.

Using this test on 110 tumour samples, the researchers were able to match men with advanced prostate cancer to a trial of olaparib with similar accuracy to traditional, more comprehensive genomic tests – but at a fraction of the cost.

This was still possible even when the samples had very few tumour cells.

The test focuses on detecting defects in tumour cell DNA repair mechanisms – and also includes other genes critically important to prostate cancer development.

Targeted drugs act on specific vulnerabilities in cancer cells, which means they are often kinder and cause fewer side effects than conventional chemotherapy.

The samples came from men with metastatic ‘castration-resistant’ prostate cancer – meaning that their cancers no longer respond to conventional hormone treatments. Being able to provide these patients with targeted treatments could give them valuable extra time with their loved ones.

Professor Johann de Bono, Regius Professor of Cancer Research at the ICR and Consultant Medical Oncologist at The Royal Marsden, said: “Being able to identify patients who would benefit from targeted therapies is very important in the treatment of advanced prostate cancer. With this study, we have shown that it is possible to match men with advanced prostate cancer to the most appropriate clinical trials using a faster, less expensive method than the one generally used. It has similar accuracy and could be used more routinely in patient care.”