Only half of bowel cancer patients know that they can receive a biomarker test for their disease, according to new research.

The multinational survey of 811 patients revealed that 52% of patients with metastatic bowel cancer were unaware of the KRAS biomarker test, which identifies they type of genetic mutation responsible for their cancer.

Almost a third (32%) was also unaware that these types of tests exist, and can help to determine which treatment could be most suitable for them.

The survey, sponsored by Merck Serono and undertaken by Ipsos MORI, was presented at the ESMO cancer congress this week.

Merck funds a biomarker test for the KRAS wild-type gene in a number of countries – including the UK – which can help determine if patients can benefit from using the firm’s drug Erbitux (cetuximab), which has licences to treat certain bowel cancers and head and neck cancers.  

In patients with metastatic colorectal cancer (mCRC), the survey found that almost half remain unaware that a KRAS biomarker test can determine whether a targeted therapy – such as Erbitux - could be effective for them.

In addition, 73% of mCRC patients would be willing to delay initiation of treatment by two weeks or more (the average turnaround time for KRAS test results) to be prescribed a therapy that is targeted and effective, with around a third (31%) stating they would be prepared to wait ‘as long as it takes’.

The survey also shows that nearly three quarters (73%) of mCRC patients would be willing to undergo a re-biopsy if necessary. Patients also said they would be willing to delay the start of their treatment to benefit from a targeted therapy, even if that meant undergoing a tumour re-biopsy.

Professor Sabine Tejpar, digestive oncology unit, University Hospital Gasthuisberg in Belgium, and lead study author, said: “KRAS testing and other biomarker tests can be beneficial in the management of patients, and it would be useful to have these tests conducted as early as possible.