[1] Leiden Univ, Dept Surg, Med Ctr, K6-R POB 9600, NL-2300 RC Leiden, Netherlands
[2] Leiden Univ, Dept Med Oncol, Med Ctr, Leiden, Netherlands
[3] Belgian Canc Registry, Brussels, Belgium
[4] Aarhus Univ Hosp, Dept Surg, Aarhus, Denmark
[5] Danish Colorectal Canc Grp DCCG Dk Database, Copenhagen, Denmark
[6] Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden
[7] Umea Univ, Dept Radiat Sci, Oncol, Umea, Sweden
[8] Publ Hlth England, Birmingham, W Midlands, England
[9] Publ Hlth England, York, N Yorkshire, England
[10] Natl Canc Registry Ireland, Cork, Ireland
[11] Univ Publ Navarra, Hlth Sci Dept, Pamplona, Spain
[12] Lithuanian Univ Hlth Sci, Oncol Inst, Kaunas, Lithuania
[13] Leiden Univ, Dept Clin Epidemiol, Med Ctr, Leiden, Netherlands
[14] Catharina Hosp, Dept Surg, Eindhoven, Netherlands
[15] Univ Maastricht, GROW Sch Oncol & Dev Biol, Maastricht, Netherlands
[16] Netherlands Comprehens Canc Org IKNL, Dept Res, Eindhoven, Netherlands
[17] Erasmus MC Univ, Dept Publ Hlth, Med Ctr, Rotterdam, Netherlands