1. Department of General, Visceral and Transplant Surgery University Hospital Heidelberg Heidelberg Germany
2. Liver Cancer Center Heidelberg (LCCH) University Hospital Heidelberg Heidelberg Germany
3. The Study Center of the German Surgical Society (SDGC) University Hospital Heidelberg Heidelberg Germany
4. Institute of Medical Biometry and Informatics (IMBI) University of Heidelberg Heidelberg Germany
5. Department of Surgery and Transplantation University Hospital RWTH Aachen Aachen Germany
6. Department of Surgery Charité –Universitätsmedizin Berlin Berlin Germany