1. Department of Gastroenterology and Hepatology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
2. Department of Surgery, Haaglanden Medical Center, 2512 VA The Hague, The Netherlands
3. Department of Surgery, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
4. Department of Gastroenterology and Hepatology, Erasmus MC Cancer Institute, University Medical Center, 3015 GD Rotterdam, The Netherlands
5. Department of Gastroenterology and Hepatology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
6. Department of Surgery, IJsselland Hospital, 2906 ZC Capelle aan den IJssel, The Netherlands