1. Digestive Oncology Research CenterDigestive Diseases Research Institute, Tehran University of Medical Sciences Tehran Iran
2. Surveillance and Health Services ResearchAmerican Cancer Society Atlanta GA
3. Digestive Disease Research CenterDigestive Diseases Research Institute, Tehran University of Medical Sciences Tehran Iran
4. Liver and Pancreatobiliary Diseases Research CenterDigestive Diseases Research Institute, Tehran University of Medical Sciences Tehran Iran
5. Gastroenterology Research CenterGolestan University of Medical Science Gorgan Iran
6. Department of Biology, School of ComputerMathematical, and Natural Sciences, Morgan State University Baltimore MD
7. Metabolic Epidemiology Branch, Division of Cancer Epidemiology and GeneticsNational Cancer Institute Bethesda MD
8. International Agency for Research on Cancer Lyon France
9. Department of Oncology, Strangeways Research LaboratoryUniversity of Cambridge Cambridge United Kingdom
10. Cancer Research UK Cambridge Institute, University of CambridgeLi Ka Shing Centre Cambridge United Kingdom
11. Department of Public Health and Primary CareUniversity of Cambridge Cambridge United Kingdom
12. Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai New York NY