1. Department of Gastrointestinal-, Thoracic- and Vascular Surgery, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
2. German Cancer Consortium, Heidelberg, Germany
3. German Cancer Research Center (DKFZ), Heidelberg, Germany
4. Department of Surgery, Universitätsmedizin Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany