[1] Centre for Gastroenterology,Department of Infectious Disease Epidemiology
[2] Neuroendocrine Tumour Unit,Department of Radiology
[3] Centre for Gastroenterology,undefined
[4] Royal Free Hospital NHS Foundation Trust,undefined
[5] School of Public Health,undefined
[6] Faculty of Medicine,undefined
[7] Imperial College London,undefined
[8] Royal Free Hospital NHS Foundation Trust,undefined
[9] UCL Cancer Institute,undefined
[10] University College London,undefined