[1] Karolinska Univ Hosp, Karolinska Inst, Dept Mol Med & Surg, Surg Care Sci, NS 67,2nd Floor, SE-17176 Stockholm, Sweden
[2] Karolinska Inst, Upper Gastrointestinal Surg, Dept Mol Med & Surg, Stockholm, Sweden
[3] Kings Coll London, Div Canc Studies, London, England
[4] Guys & St Thomas NHS Fdn Trust, London, England
[5] Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden
[6] Uppsala Univ, Clin Psychol Healthcare, Dept Womens & Childrens Hlth, Uppsala, Sweden