[1] Univ Verona Hosp Trust, Pancreas Inst, Unit Surg B, I-37134 Verona, Italy
[2] Tech Univ Munich, Klinikum Rechts Isar, Dept Surg, D-80290 Munich, Germany
[3] Tech Univ Munich, Klinikum Rechts Isar, Dept Gastroenterol, D-80290 Munich, Germany
[4] Ege Univ, Dept Internal Med, Div Gastroenterol, Izmir, Turkey
[5] IRCCS Policlin San Matteo, Dept Surg, Unit Gen Surg 2, Pavia, Italy
[6] Karolinska Univ Hosp, Karolinska Inst, CLINTEC, Div Surg, Stockholm, Sweden
[7] Karolinska Univ Hosp, Karolinska Inst, CLINTEC, Div Gastroenterol, Stockholm, Sweden
[8] European Inst Oncol, Div Epidemiol & Biostat, Milan, Italy