1. Medical Department 1, Johannes Gutenberg University, Mainz, Germany
2. Department of Gastroenterology, Hospital Darmstadt GmbH, Darmstadt, Germany
3. Department of Medical Oncology, West German Cancer Center, University Hospital Essen, Essen, Germany
4. Hematological and Oncological Practice Eppendorf (HOPE), Practice for Oncology, Hamburg, Germany
5. Practice for Hematology and Oncology, Müllheim a.d.R., Germany
6. Oncologianova GmbH Recklinghausen, Recklinghausen, Germany
7. Department of Medicine I, Nordoberpfalz Clinics AG, Weiden i.d.O, Germany
8. Department of General and Visceral Surgery, Frankfurt University Hospital and Clinics, Frankfurt, Germany
9. Department of Hematology and Oncology, Robert Bosch Hospital, Stuttgart, Germany
10. Department of Surgery, Campus Charité Mitte and Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Berlin, Germany
11. University Cancer Center Leipzig (UCCL), University Hospital Leipzig, Leipzig, Germany
12. Department of Medical Oncology and Comprehensive Cancer Center, University Hospital Grosshadern, Ludwig Maximilian University of Munich, Munich, Germany
13. Department of Internal Medicine, Oncology/Hematology, Gastroenterology, Hospital Esslingen GmbH, Esslingen, Germany
14. Department of Hematology and Oncology, Hospital Altenburger Land GmbH, Altenburg, Germany
15. Department of Hematology/Oncology, Klinikum Darmstadt GmbH, Darmstadt, Germany
16. Clinic of Visceral Surgery, Municipal Hospital Karlsruhe gGmbH, Karlsruhe, Germany
17. Department of Internal Medicine III, Paracelsus Medical University Salzburg, Salzburg Cancer Research Institute-CCCIT, Cancer Cluster, Salzburg, Austria
18. Department of General, Visceral and Transplantation Surgery, University Hospital of Mainz, Mainz, Germany
19. Institute for Medical Biostatistics, Epidemiology and Informatics, Johannes Gutenberg-University Mainz, Mainz, Germany