1. Humanitas University and IRCCS Istituto Clinico Humanitas; Rozzano Italy
2. Gastroenterology and Hepatology Unit, Di.Bi.M.I.S.; University of Palermo; Palermo Italy
3. Gastroenterology and Hepatology Unit; Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico; Milan Italy
4. Department of Medicine; ASST Nord Milano; Milan Italy
5. Department of Internal Medicine; A.O. Santi Paolo e Carlo; Milan Italy
6. Department of Surgery and Integrated Diagnostics; University of Genoa; Genoa Italy
7. Division of Epidemiology and Biostatistics; European Institute of Oncology; Milan Italy