1. Faculty of Medicine, Albert-Ludwigs-University of Freiburg, 79110 Freiburg im Breisgau, Germany
2. Department of General and Visceral Surgery, University Medical Center Freiburg, 79106 Freiburg im Breisgau, Germany
3. Tumorbank, Comprehensive Cancer Center Freiburg, University Medical Center Freiburg, 79106 Freiburg im Breisgau, Germany
4. Institute for Surgical Pathology, University Medical Center Freiburg, 79106 Freiburg im Breisgau, Germany
5. Department of Surgery, University Medical Center Schleswig-Holstein, 23538 Lübeck, Germany