1. 1Division of Medicine, Department of Metabolism and Experimental Therapeutics, University College London, London, UK
2. 2Department of Endocrinology, OCDEM, University of Oxford, Oxford, UK
3. 3Neuroendocrine Tumour Unit, Royal Free Hospital, London, UK
4. 4Centre for Endocrinology, Barts and the London School of Medicine, Queen Mary University of London, London, UK
5. 5Department of Diabetes and Endocrinology, University College London Hospital NHS Foundation Trust, London, UK
6. 6Division of Medicine, University College London, London, UK
7. 7Centre for Neuroendocrinology, Royal Free Campus, University College London, London, UK
8. 8First Department of Propaedeutic and Internal Medicine, Laiko University Hospital, National and Kapodistrian University of Athens, Athens, Greece