1. Department of Surgical, Oncological and Oral Sciences, University of Palermo, 90127 Palermo, Italy
2. Department of Surgical Sciences, University of Cagliari, 09124 Cagliari, Italy
3. Postgraduate School of General Surgery, University of Palermo, 90127 Palermo, Italy
4. CEMERIT (Centro Meridionale Ricerca e Training), IZSS, 90129 Palermo, Italy