[1] Univ Oulu, Oulu Univ Hosp, Med Res Ctr Oulu, Surg Res Unit, Oulu, Finland
[2] Oulu Univ Hosp, Dept Surg, Kajaaninkatu 50, Oulu 90220, Finland
[3] Cent Finland Cent Hosp, Dept Surg, Jyvaskyla, Finland
[4] Turku Univ Hosp, Div Digest Surg & Urol, Turku, Finland
[5] Oulu Univ Hosp, Dept Oncol & Radiotherapy, Oulu, Finland
[6] Univ Helsinki, Helsinki Univ Hosp, Dept Surg, Helsinki, Finland
[7] Univ Oulu, Oulu Univ Hosp, Med Res Ctr Oulu, Canc & Translat Med Res Unit, Oulu, Finland
[8] Univ Eastern Finland, Kuopio Univ Hosp, Dept Surg, Kuopio, Finland
[9] Univ Helsinki, Helsinki Univ Hosp, Dept Pathol & HUSLAB, Helsinki, Finland
[10] Univ Helsinki, Appl Tumor Genom Res Program, Res Programs Unit, Helsinki, Finland
[11] Univ Helsinki, Helsinki Univ Hosp, Heart & Lung Ctr, Dept Gen Thorac & Oesophageal Surg, Helsinki, Finland
[12] Univ Tampere, Tampere Univ Hosp, Heart Ctr, Dept Cardiothorac Surg, Tampere, Finland
[13] Tampere Univ Hosp, Dept Gastroenterol & Alimentary Tract Surg, Tampere, Finland
[14] Karolinska Univ Hosp, Karolinska Inst, Dept Mol Med & Surg, Upper Gastrointestinal Surg, Stockholm, Sweden