1. Royal Free Campus, UCL Medical School; Department of Surgery; Royal Free Hospital Rowland Hill Street London UK NW3 2PF
2. University College London; Department of General Surgery; 4th Floor, Rockefeller Building 21 University Street London UK WC1E 6DE
3. King's College London School of Medicine; Division of Cancer Studies, Cancer Epidemiology Group; Guy's Hospital, Great Maze Pond Research Oncology London UK SE1 6RT
4. Royal Berkshire Hospital; Department of General Surgery; Reading UK RG1 5AN
5. University College London; Division of Surgery and Interventional Science; London UK
6. University College Hospital; London UK