1. Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Study of Campania, “Luigi Vanvitelli”, 83138 Naples, Italy
2. Department of Surgical Sciences, University of Turin, 10124 Torino, Italy
3. Department of General Surgery and Surgical-Medical Specialties, University of Catania, Via S. Sofia 78, 95123 Catania, Italy