1. Attikon University Hospital Third Department of Surgery, National and Kapodistrian University of Athens, , Athens, Greece
2. National and Kapodistrian University of Athens, Hippokration General Hospital First Propaedeutic Department of Surgery, , Athens, Greece
3. University Medical Center Utrecht Department of Surgery, , Utrecht, The Netherlands
4. Lausanne University Hospital (CHUV) Department of Visceral Surgery, Faculty of Biology and Medicine UNIL, , Lausanne, Switzerland
5. The Ohio State University Wexner Medical Center, James Comprehensive Cancer Center Department of Surgery, , Columbus, OH, USA
6. Attikon University Hospital Second Department of Neurology, National and Kapodistrian University of Athens, , Athens, Greece
7. National and Kapodistrian University of Athens, Laikon General Hospital First Department of Surgery, , Athens, Greece