G Pellino1,2, M Podda3, F Pata4,5, S Di Saverio6, B Ielpo7. 1. Department of Advanced Medical and Surgical Sciences, Universitá degli Studi della Campania 'Luigi Vanvitelli', Naples, Italy. 2. Colorectal Surgery, Vall d'Hebron University Hospital, Barcelona, Spain. 3. Department of General and Emergency Surgery, Cagliari University Hospital, Cagliari, Italy. 4. General Surgery Unit, Nicola Giannettasio Hospital, Corigliano-Rossano, Italy. 5. La Sapienza University, Rome, Italy. 6. ASUR Marche 5, San Benedetto del Tronto General Hospital, University Hospital of Varese, ASST Sette Laghi, Regione Lombardia, Varese, Italy. 7. Department of Surgery, HPB Unit, Hospital del Mar - Parc de Salut MAR, University Pompeu Fabra, Barcelona, Spain.