1. Department of General, Visceral and Transplantation Surgery, Charité Campus Virchow Clinic, Humboldt University of Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
2. Department of Gastroenterology and Hepatology, Division of Central Interdisciplinary Endoscopy, Charité Campus Virchow Clinic, Humboldt University of Berlin, Augustenburger Platz 1, 13353 Berlin, Germany