[1] Karolinska Univ Hosp, Karolinska Inst, Dept Clin Sci Intervent & Technol, Div Surg, Stockholm, Sweden
[2] Karolinska Univ Hosp, Ctr Digest Dis, K53, S-14186 Stockholm, Sweden
[3] Karolinska Univ Hosp, Karolinska Inst, Dept Oncol, S-14186 Stockholm, Sweden
[4] Karolinska Univ Hosp, Karolinska Inst, Dept Pathol, S-14186 Stockholm, Sweden
[5] Univ Trondheim Hosp, St Olavs Hosp, Dept Gastrointestinal Surg, Trondheim, Norway
[6] Oslo Univ Hosp, Dept Oncol, N-0450 Oslo, Norway
[7] Univ Trondheim Hosp, Dept Oncol, St Olavs Hosp, N-7006 Trondheim, Norway
[8] Haukeland Hosp, Dept Oncol, N-5021 Bergen, Norway
[9] Malarsjukhuset Eskilstuna, Karolinska Inst, Dept Oncol, Stockholm, Sweden