1. HPB Unit, Department of Surgery, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
2. Department of General Surgery, Croydon University Hospital, Croydon Health Services NHS Trust, London CR7 7YE, UK
3. Department of Anatomy-Histology-Embryology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
4. Department of Pathology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
5. Department of Gastroenterology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece