1. Departments of General, Visceral, and Transplantation Surgery, Essen, Germany
2. Department of Surgery, North Shore University Hospital, Manhasset, New York
3. Departments of Diagnostic and Interventional Radiology and Neuroradiology, Essen, Germany
4. Institute of Pathology and Neuropathology, Essen, Germany
5. Department of Gastroenterology and Hematology, University Hospital Essen, Essen, Germany