1. Department of Gastrointestinal Surgery, Clinic of Surgery, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
2. Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
3. Department of Registration, Cancer Registry of Norway, Oslo, Norway
4. Department of Research, Møre and Romsdal Hospital Trust, Ålesund, Norway