1. Department of Surgery, Charité ? University Medicine Berlin, Campus Mitte/Campus Virchow-Klinikum, Berlin, Germany;
2. Department of General, Visceral, Vascular and Bariatric Surgery, KRH-Klinikum Nordstadt, Klinikum Region Hannover GmbH, Hannover, Germany;
3. Department of Radiation Oncology, Charité – Universitätsmedizin Berlin, Campus Mitte, Berlin, Germany