1. Department of Surgery; Ersta Hospital; Karolinska Institutet; Danderyds Hospital; Stockholm Sweden
2. Department of Surgery and Gastroenterology; Park Leopold Clinic; CHIREC; Brussels Belgium
3. CHU Hotel Dieu Institut des Maladies de l' Appareil Digestif; Nantes France
4. Department of Gastroenterology; University Hospitals Leuven; Leuven Belgium
5. Department of Surgery; Centre for Digestive Diseases; Karolinska University Huddinge Hospital; Karolinska Institutet; Stockholm Sweden