[1] Klinikum St Georg, Klin Allgemein & Visceralchirurg, Leipzig, Germany
[2] San Raffaele Univ, Dept Surg, Milan, Italy
[3] Semmelweis Univ, Dept Surg 1, Budapest, Hungary
[4] Univ Roma La Sapienza, Dept Clin Med, Rome, Italy
[5] Karolinska Univ Hosp Huddinge, Div Surg, CLINTEC, Karolinska Inst, Stockholm, Sweden
[6] Ersta Hosp, Ctr Gastrointestinal Dis, Stockholm, Sweden
[7] Acad Hosp Maastricht, Dept Surg, Maastricht, Netherlands