1. Section for Colorectal Surgery, Ullevaal, Norway
2. Department of Gastrointestinal and Paediatric Surgery, Oslo University Hospital, Ullevaal, Norway
3. Section for Abdominal and Oncological Radiology, Department of Radiology, Oslo University Hospital, Ullevaal/Aker, Norway
4. Faculty of Medicine, University of Oslo, Oslo, Norway
5. Section for Upper Gastrointestinal Surgery, Department of Gastrointestinal and Paediatric Surgery, Oslo University Hospital, Ullevaal, Norway