1. Department of Surgery Cantonal Hospital Olten Olten Switzerland
2. Department of General, Visceral and Vascular Surgery, Campus Benjamin Franklin Charité University of Medicine Berlin Germany
3. Department of Surgery Hospital Center Biel Biel/Bienne Switzerland
4. Department of Surgery Hospital Limmattal Schlieren Switzerland
5. Department of Oncology and Hematology Cantonal Hospital St. Gallen Switzerland
6. Institute of Medical Biometry and Informatics University of Heidelberg Germany
7. Medical Oncology & Hematology Center Hospital Thun Switzerland
8. Department of Oncology and Hematology Cantonal Hospital Olten Switzerland
9. Clarunis Visceral Surgery Center, St. Clara Hospital & University Hospital Basel Basel Switzerland