1. Department of Colorectal Surgery, The Royal Free Hospital, Pond Street, Hampstead, London NW3 2QG, UK
2. University College London Medical School, 74 Huntley Street, London WC1E 6DE, UK
3. Division of Surgery and Interventional Science, University College London, Royal Free Hospital Campus, 9th Floor, Pond Street, Hampstead, London NW3 2QG, UK
4. Neuroendocrine Tumour Unit, The Royal Free Hospital, Pond Street, Hampstead, London NW3 2QG, UK