1. Department of General, Visceral and Thoracic Surgery, University Hospital Hamburg-Eppendorf , Hamburg 20246 , Germany
2. Mildred Scheel Cancer Career Center , Hamburg 20246 , Germany
3. Institute of Tumor Biology, University Hospital Hamburg-Eppendorf , Hamburg 20246 , Germany
4. Clinic for Stem Cell Transplantation, University Hospital Hamburg-Eppendorf , Hamburg 20246 , Germany
5. II. Medical Clinic and Polyclinic (Oncology), University Hospital Hamburg-Eppendorf , Hamburg 20246 , Germany
6. Department of Pathology, University Medical Center, University of Groningen , Groningen 9700 RB , Netherlands
7. Institute of Pathology, University Hospital Hamburg-Eppendorf , Hamburg 20246 , Germany