1. Endocrine Oncology Unit, 1st Department of Propaupedic Internal Medicine, Laiko Hospital National and Kapodistrian University of Athens Athens Greece
2. Department of Surgical Sciences Uppsala University Uppsala Sweden
3. Gastroenterology Division, Department of Pathophysiology, Laikon University Hospital National and Kapodistrian University of Athens Athens Greece
4. Department of Gastroenterology “G. Gennimatas” General Hospital Athens Greece