[1] Karolinska Institutet,Upper Gastrointestinal Surgery, Department of Molecular Medicine and Surgery
[2] Norwegian University of Science and Technology,European Palliative Care Research Centre, Department of Cancer Research and Molecular Medicine
[3] Norwegian University of Science and Technology,HUNT Research Centre, Department of Public Health and General Practice
[4] King’s College London,Division of Cancer Studies
[5] Imperial College London,Department of Epidemiology and Biostatistics