Annarita Libia1,2, Valentina Ferraro3, Riccardo Memeo3. 1. Department of Surgical Sciences, Sapienza University of Rome, Rome, Italy. libiamd@me.com. 2. Hepatobiliary and Pancreatic Surgery Unit, Hospital F. Miulli, Acquaviva delle Fonti, Bari, Italy. libiamd@me.com. 3. Hepatobiliary and Pancreatic Surgery Unit, Hospital F. Miulli, Acquaviva delle Fonti, Bari, Italy.