1. Department of Gastroenterology, Oncology and Diabetology, Theresienkrankenhaus and Sankt Hedwig-Klinik, Mannheim, Germany
2. Department of General, Visceral and Transplant Surgery, Tübingen University Hospital, Tübingen, Germany
3. Department of General and Abdominal Surgery, Theresienkrankenhaus and Sankt Hedwig-Klinik, Mannheim, Germany
4. Department of Gastroenterology, Klinikum der Stadt Ludwigshafen am Rhein, Ludwigshafen, Germany
5. Department of General, Abdominal and Thoracic Surgery, Klinikum der Stadt Ludwigshafen, Ludwigshafen, Germany
6. Department of Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
7. Department of Medical Statistics, Biomathematics, and Information Processing, University Hospital Mannheim, Mannheim, Germany
8. Department of Gastroenterology, Hepatology and Infectiology, University Hospital Mannheim, Mannheim, Germany
9. Department of Surgery, University Hospital Mannheim, Mannheim, Germany