1. Department of Surgery; Virgen del Camino Hospital; Public University of Navarra; Pamplona Spain
2. Department of Surgery; St Olavs Hospital; Trondheim University Hospital; Trondheim Norway
3. Department of Cancer Research and Molecular Medicine; Norwegian University of Science and Technology; Trondheim Norway
4. Department of Surgery; Hospital Universitario Virgen de la Arrixaca; Murcia Spain
5. Department of Surgery; University Hospital of Girona Dr J. Trueta; Girona Spain
6. Department of General and Digestive Surgery; Colorectal Unit; Bellvitge University Hospital; University of Barcelona and IDIBELL; Barcelona Spain