1. 1Department of Gastrointestinal Oncology, The Netherlands Cancer Institute, Amsterdam, the Netherlands.
2. 2Department of Public Health, Erasmus University Medical Center, Rotterdam, the Netherlands.
3. 3Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, the Netherlands.
4. 4Department of Gastroenterology and Hepatology, University Medical Center Utrecht, Utrecht, the Netherlands.
5. 5Department of Gastroenterology and Hepatology, Radboud University Medical Center, Nijmegen, the Netherlands.
6. 6Department of Medical Oncology, Netherlands Cancer Institute, Amsterdam, the Netherlands.
7. 7Department of Hematology, Erasmus University, Rotterdam, the Netherlands.
8. 8Department of Radiation Oncology, Erasmus University Medical Center, Rotterdam, the Netherlands.
9. 9Department of Hematology, University Medical Center Utrecht, Utrecht, the Netherlands.
10. 10Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, the Netherlands.
11. 11Department of Radiation Oncology, Radboud University Medical Center, Nijmegen, the Netherlands.
12. 12Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam, the Netherlands.
13. 13Department of Pathology, Netherlands Cancer Institute, Amsterdam, the Netherlands.
14. 14Department of Epidemiology, Netherlands Cancer Institute, Amsterdam, the Netherlands.
15. 15Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, the Netherlands.