1. Department of Surgery, Macerata Hospital, Macerata, Italy.
2. St. Orsola–Malpighi University Hospital, Bologna, Italy.
3. Department of Surgery, San Donato Hospital, Arezzo, Italy.
4. Department of Surgery, Savona Hospital, Savona, Italy.
5. Department of General Vascular and Minimally Invasive Surgery, Spoleto Hospital, Spoleto, Italy.
6. Department of Surgery, Trento Hospital, Trento, Italy.
7. Department of Surgery, Adria Hospital, Adria, Italy.
8. Policlinico Gemelli Hospital, Rome, Italy.
9. Policlinico Umberto I Hospital, Rome, Italy.
10. Riuniti Hospital, Foggia, Italy.
11. Department of Surgery, Rummo Hospital, Benevento, Italy.
12. Department of Surgery, Garibaldi Hospital, Catania, Italy.