[1] Gen Univ Hosp Larisa, Dept Gastroenterol, Larisa 41110, Greece
[2] Aristotle Univ Thessaloniki, Sch Med, Lab Pharmacol 1, Thessaloniki 54124, Macedonia, Greece
[3] St Marks Hosp & Acad Inst, Wolfson Unit Endoscopy, London, England
[4] Erasme Univ Hosp, Dept Gastroenterol Hepatopancreatol & Digest Onco, B-1070 Brussels, Belgium
[5] Barking Havering & Redbridge Univ Hosp NHS Trust, Digest Dis Ctr, London, England
[6] Imperial Coll London, Dept Surg & Canc, London, England
[7] Royal Free Hosp, Neuroendocrine Tumour Unit, ENETS Ctr Excellence, Ctr Gastroenterol, London, England