1. Department of General Surgery; Sheffield Teaching Hospitals; Sheffield UK
2. Department of Oncology and Metabolism; Medical School; University of Sheffield; Sheffield UK
3. South Yorkshire Surgical Research Group; Department of General Surgery; Northern General Hospital; Sheffield UK
4. University Hospital South Manchester; Manchester UK
5. North-West Research Collaborative; University Hospital South Manchester; Manchester UK
6. St James University Hospital; Leeds UK
7. Addenbrooke's Hospital; Cambridge UK