Research from the University of Southampton has shown a drug, used in combination with chemotherapy to treat advanced colorectal cancer, is not effective in some settings, and indeed may result in more rapid cancer progression.

The New EPOC study, published in The Lancet Oncology and funded by Cancer Research UK, evaluated whether the drug cetuximab and chemotherapy together worked better than chemotherapy alone as a treatment in addition to surgery for people with bowel cancer that had spread to the liver but could be surgically removed. In the trial patients either received chemotherapy on its own or chemotherapy combined with cetuximab. Patients received their specified treatment for 12 weeks. They then had surgery and followed by their specified treatment for another 12 weeks. Patients were then monitored via CT or MRI scans.

The researchers found that adding cetuximab to chemotherapy did not help this group of people. Analysis looked at how long people in each group were living without any sign of their cancer getting worse. They found this was on average 14.1 months in the group having chemotherapy and cetuximab compared to 20.5 months in the group having chemotherapy alone.

John Primrose, Professor of Surgery at the University of Southampton, comments: "These results were unexpected. Cetuximab is already approved by NICE alongside chemotherapy for people who had bowel cancer that had spread to the liver if the oncologist and liver surgeon thought this would enable the patient to have a liver operation. The cetuximab and chemotherapy combination is also used successfully in patients whose disease cannot be operated on at all. Our trial tested it in people who had cancer spread to the liver who were suitable for surgery from the outset, a similar group, but for these patients it seems to have an adverse effect. More research is needed to understand this surprising result."

Professor Primrose, also a consultant surgeon at Southampton General Hospital, adds: "These are very important data and we would like to thank the patients and relatives of patients those who took part in this trial, as well as the many clinicians in the UK who participated. Our results demonstrate the importance of clinical trials to ensure patients with cancer receive the best of treatment for their condition."