Cetuximab, used in combination with chemotherapy to treat advanced colorectal cancer (CRC), is not effective in some settings and may even result in more rapid cancer progression.
Becacse Cetuximab is known to have activity in patients with CRC with the KRAS exon 2 wild-type, this population of patients was enrolled in the study. Researchers evaluated whether the drug cetuximab and chemotherapy together worked better than chemotherapy alone, in addition to surgery, for patients whose CRC had spread to the liver but could be surgically removed.
In this trial, which was published in The Lancet Oncology (2014; doi:10.1016/S1470-2045(14)70105-6), patients received either chemotherapy alone or chemotherapy combined with cetuximab. Patients then had surgery and followed their specified treatment for another 12 weeks. Patients were then monitored through computed tomography or magnetic resonance imaging scans.
The researchers found that adding cetuximab to chemotherapy did not help this group of patients. Their analysis looked at how long patients in each group were living without progression of disease. On average, progression-free survival was 14.1 months in the group receiving chemotherapy and cetuximab compared to 20.5 months in the group receiving chemotherapy alone.
“These results were unexpected. Cetuximab is already approved by NICE [National Institute for Clinical Excellence] 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,” said John Primrose, MD, Professor of Surgery at the University of Southampton, United Kingdom. “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.”
Primrose added, “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.”