1. Department of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland.
2. Division of Gastroenterology and Hepatology, Stadtspital Zurich, Zurich, Switzerland.
3. Department of Radiation Oncology and Competence Centre for Palliative Care, University Hospital Zurich, Zurich, Switzerland.
4. Gastroenterology and Hepatology Unit, Luzerner Kantonsspital, Lucerne, Switzerland.