1. Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, the Netherlands
2. Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
3. Department of Surgery, Leiden University Medical Center, Leiden, the Netherlands
4. Department of Oncology, Leiden University Medical Center, Leiden, the Netherlands
5. Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands
6. Department of Clinical Genetics, Leiden University Medical Center, Leiden, the Netherlands
7. Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, the Netherlands
8. Department of Gastrointestinal Oncology, Netherlands Cancer Institute, Amsterdam, the Netherlands