1. Department of general surgery, Oxford University Hospitals National Health Service Foundation Trust , Oxford , UK
2. Department of General Surgery, University of Witwatersrand , Johannesburg , South Africa
3. Department of Surgery and Cancer, Imperial College London, St Mary’s Hospital , London , UK
4. Department of Surgery, McGill University Health Centre , Montreal, Quebec , Canada
5. Department of Surgery, Univeristy of Birmingham National Health Service Trust , Birmingham , UK
6. Department of Thoracic Surgery and Thoracic Oncology, Virginia Mason Medical Centre , Seattle, Washington , USA
7. Department of Surgery, Oxford Upper GI Centre, Churchill Hospital, Oxford University Hospitals National Health Service Foundation Trust , Oxford , UK
8. Section of Gastrointestinal Surgery , Department of Surgery, , Barcelona , Spain
9. Hospital del Mar Medical Research Institute , Department of Surgery, , Barcelona , Spain
10. Division of Surgery, UMC Amsterdam , Amsterdam
11. Department of Surgery, College of Medicine and Public Health, Flinders University , Adelaide , Australia
12. Department of Surgery , Hospital SS Giovanni e Paolo, Venezia , Italy