[1] CHU Paris Ouest, Hop Ambroise Pare, Dept Digest Surg, F-92100 Boulogne, France
[2] Univ Hosp Gasthuisberg, Digest Oncol Unit, B-3000 Louvain, Belgium
[3] Univ Vienna, Dept Gen Surg, Vienna, Austria
[4] Uppsala Univ, Dept Oncol Radiol & Clin Immunol, Uppsala, Sweden
[5] Karolinska Inst, Dept Pathol & Oncol, Stockholm, Sweden
[6] Aintree Univ Hosp NHS Fdn Trust, Dept Surg, Liverpool L9 7AL, Merseyside, England
[7] San Martino Hosp, Genoa, Italy
[8] CRLC Val Aurelle, Montpellier 05, France