1. Postgraduate School of General Surgery, University of Cagliari, Cagliari, Italy;
2. Department of General Surgery, University of Cagliari, Cagliari, Italy;
3. Department of Pathologic Anatomy and Histology, University of Palermo, Palermo, Italy;
4. Department of Pathologic Anatomy and Histology, IZSS Palermo, Palermo, Italy;
5. Department of General Surgery and Urgency, University of Palermo, Palermo, Italy