1. Department of Oncology, Akershus University Hospital, Lørenskog, Norway
2. Institute of Clinical Medicine, University of Oslo, Oslo, Norway
3. Institute of Clinical Molecular Biology, Akershus University Hospital, Lørenskog, Norway
4. Department of Oncology, Oslo University Hospital, Norwegian Radium Hospital, Oslo, Norway
5. Department of Tumor Biology, Oslo University Hospital, Norwegian Radium Hospital, Oslo, Norway
6. Department of Gastroenterological Surgery, Oslo University Hospital, Norwegian Radium Hospital, Oslo, Norway