This study is a multi-centre retrospective observational research study which will be conducted in UK centres with specialised liver surgical services.

The study will involve retrospective review of medical records of patients with metastatic colorectal cancer (mCRC) with metastases confined to the liver, defined locally as unresectable without downsizing therapy at first review by a Hepatobiliary Multi Disciplinary Team (HPB MDT). Erbitux is available for use in combination with chemotherapy as a downsizing treatment for patients with previously unresectable metastases.

The study aims to examine liver resection rates achieved in normal clinical practice in order to inform National Health Service (NHS) clinical and policy decision making and to further understanding of how cetuximab is used in a standard clinical setting. This study intends to estimate the proportion of patients with unresectable liver metastases who undergo liver resection following downsizing treatment with chemotherapy plus cetuximab.

Inclusion Criteria:

• Patients who had mCRC and metastases confined to the liver
• Patients in whom downsizing regimens are recommended
• Patients in whom downsizing treatment included cetuximab
• Patients referred to Hepatobiliary Multi Disciplinary Team (HPB MDT) between 01.01.2010-31.03.2011

Exclusion Criteria:

• Patients who are considered to have immediately resectable liver metastases as determined by the HPB MDT
• Patients who are considered to have never resectable liver metastases as determined by the HPB MDT
• Patients who were aged less than 18 at date of initiation of cetuximab
• Patients who are enrolled in a clinical trial during the data collection period
• Patients who are receiving private healthcare for the treatment of mCRC
• According to Summary of Product Characteristics (SmPC)

primary care clinic