[1] Danderyd Hosp, Karolinska Inst, Dept Clin Sci, Div Surg & Urol, Stockholm, Sweden
[2] Karolinska Univ Hosp, Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Div Med Imaging & Technol, Stockholm, Sweden
[3] Karolinska Univ Hosp, Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Div Surg, Stockholm, Sweden
[4] Karolinska Univ Hosp, Karolinska Inst, Dept Oncol Pathol, Stockholm, Sweden
[5] Univ Cape Town, Fac Hlth Sci, Groote Schuur Hosp, Surg Gastroenterol Unit,Dept Surg, Cape Town, South Africa