1 Department of Gastrointestinal Surgery, VU University Medical Center, De Boelelaan 1117, 7F 020, 1081 HV, Amsterdam, The Netherlands. je.straatman@vumc.nl.
2 Department of Gastrointestinal Surgery, VU University Medical Center, De Boelelaan 1117, 7F 020, 1081 HV, Amsterdam, The Netherlands.