1. Division of Clinical Epidemiology and Aging Research German Cancer Research Center (DKFZ) Heidelberg 69120 Germany
2. Medical Faculty Heidelberg of Heidelberg University Heidelberg 69120 Germany
3. German Cancer Consortium German Cancer Research Center Heidelberg 69120 Germany
4. Department of Research & Development Netherlands Comprehensive Cancer Organization Utrecht 3501 DB The Netherlands
5. Department of Medical Oncology Amsterdam University Medical Centers Amsterdam 1105 AZ The Netherlands
6. Department of Surgery University Medical Center Utrecht Utrecht 3508 GA The Netherlands
7. Belgian Cancer Registry Brussels B‐1210 Belgium
8. Department of Esophageal and Gastric Surgery Lund University Hospital Lund 221 85 Sweden
9. Department of Clinical Science Intervention, and Technology, Division of Surgery Karolinska University Hospital Stockholm 171 76 Sweden
10. Registry Department The Cancer Registry of Norway Oslo 0379 Norway
11. Epidemiology and Cancer Registry Institute of Oncology Ljubljana Ljubljana 1000 Slovenia
12. Department of Surgery Erasmus Medical Centre‐University Medical Centre Rotterdam Rotterdam 3015 CE The Netherlands
13. Department of Surgical Oncology Leiden University Medical Center Leiden 2300 RC The Netherlands
14. Division of Preventive Oncology German Cancer Research Center and National Center for Tumor Diseases Heidelberg 69120 Germany