[1] Univ Med Ctr Hamburg Eppendorf, Dept Gen Visceral & Thorac Surg, Hamburg, Germany
[2] Univ Med Ctr Hamburg Eppendorf, Dept Med Biometry & Epidemiol, Hamburg, Germany
[3] Ruhr Univ Bochum, Dept Surg, St Josef Hosp Bochum, Bochum, Germany
[4] Univ Milan, Dept Gen Surg, Inst Clin Humanitas IRCCS, Milan, Italy
[5] Univ Verona Hosp Trust, Dept Surg, Unit Surg B, Pancreas Inst,GB Rossi Hosp, Verona, Italy