1. Medizinische Klinik und Poliklinik 2, Klinikum der Universität München, Campus Grosshadern, Munich, Germany
2. Department of Gastroenterology, Endocrinology and Metabolism, University Hospital of Marburg, Philipps-University of Marburg, Marburg, Germany
3. Department of Internal Medicine and Gastroenterology, HELIOS Klinikum Berlin-Buch, Berlin, Germany
4. Department of Oncology, University of Torino, Candiolo, Torino, Italy
5. Candiolo Cancer Institute-FPO, IRCCS, Candiolo, Italy