1. University of Perugia; Department of General Surgery; Terni Italy
2. University of Perugia; Department of General Surgery; Perugia Italy
3. Regional Health Authority of Umbria; Epidemiology Department; Via Mario Angeloni, 61 Perugia Italy 06124
4. AO Mellini; Laparoscopic Surgical Unit; v.le Mazzini 4 Chiari (BS) Italy 25032
5. Regional Health Authority of Umbria; Health Planning Service; Via Mario Angeloni 61 Perugia Umbria Italy 06124
6. Hospital of Terni; Liver Unit and Department of Digestive Surgery; Terni Italy
7. Saint John of God Hospital Subiaco; Colorectal Cancer Unit.; McCourt Street Subiaco Perth Western Australia Australia 6008