1. 3rd Surgical Department, University General Hospital of Thessaloniki “AHEPA”, Aristotle University of Thessaloniki, 1st St. Kiriakidi Street, 54621 Thessaloniki, Greece
2. Department of Pathology, School of Medicine, Aristotle University of Thessaloniki, 54621 Thessaloniki, Greece
3. European Interbalkan Medical Center, 10 Asklipiou Street, 55535 Pylaia, Greece
4. Department of Medicine, Medical University of Plovdiv, y.B.Apo15A, 4002 Plovdiv, Bulgaria
5. Faculty of Health Sciences, Medical School, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
6. Faculty of Health Sciences, Medical School, University of Ioannina, 45110 Ioannina, Greece