1. Division of Oncology, Department of Internal Medicine and Oncology, Semmelweis University, H-1083 Budapest, Hungary
2. Department of Surgery, University Medical Center Regensburg, D-93053 Regensburg, Germany
3. Department of Internal Medicine and Hematology, Semmelweis University, H-1088 Budapest, Hungary
4. Department of Finance, Rutgers University, Newark, NJ 07102, USA
5. Department of General and Visceral Surgery, Hospital Barmherzige Brüder, D-93049 Regensburg, Germany