1 Division of Digestive Surgery and Urology, Turku University Hospital, Turku, Finland. anna.junttila@fimnet.fi.
2 Surgery Research Unit, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
3 Upper Gastrointestinal Surgery, Department of Molecular Medicine and Surgery, Karolinska Insitutet and Karolinska University Hospital, Stockholm, Sweden.