1. Institute of Pathology, University Medical Center Göttingen, Göttingen, Germany
2. Department of Radiotherapy and Oncology, University of Frankfurt, Frankfurt, Germany
3. Department of Medical Statistics, University Medical Center Göttingen, Göttingen, Germany
4. Institute of Pathology, University Medical Center Leipzig, Leipzig, Germany
5. Institute of Pathology, University Medical Center Erlangen, Erlangen, Germany
6. Institute of Pathology Nordhessen, Kassel, Germany
7. Institute of Pathology, Klinikum Nürnberg Nord, Nuremberg, Germany
8. Institute of Pathology, Mönchengladbach, Germany
9. Department of General and Visceral Surgery, Krankenhaus Maria Hilf, Mönchengladbach, Germany
10. Department of Visceral Surgery, University Medical Center Regensburg, Regensburg, Germany
11. Department of Visceral Surgery, Asklepios Paulinen Klinik Wiesbaden, Wiesbaden, Germany
12. Department of General and Visceral Surgery, University Medical Center Frankfurt, Frankfurt, Germany
13. Department of General and Visceral Surgery, University Medical Center Oldenburg, Oldenburg, Germany
14. Department of General and Visceral Surgery, Klinikum Esslingen, Esslingen, Germany
15. Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
16. Department of General and Visceral Surgery, University Medical Center Göttingen, Göttingen, Germany
17. Department of Radiation Therapy, University of Erlangen, Erlangen, Germany
18. Department of General and Visceral Surgery, University of Erlangen, Erlangen, Germany