1. Department of General, Visceral and Transplant Surgery, University of Tübingen, Tübingen, Germany
2. Department of General, Visceral and Transplant Surgery, University Hospital Tuebingen, Tübingen, Germany
3. Institute of Pathology, University of Tübingen, Tübingen, Germany
4. Department of Internal Medicine VIII, University of Tübingen, Tübingen, Germany