1. Department of Oncology, University and General Hospital, Udine, Italy
2. Department of Oncology, S.Orsola-Malpighi Hospital, Bologna, Italy
3. Gastrointestinal Medical Oncology Unit, National Cancer Institute “Fondazione Giovanni Pascale”-IRCCS, Napoli, Italy
4. Department of Oncology, National CancerInstitute “Giovanni Paolo II”-IRCSS, Bari, Italy
5. Unit of Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy
6. Department of Oncology, Careggi Hospital, Firenze, Italy
7. Department of Medical Oncology, University of Torino, Candiolo Cancer Institute-FPO-IRCCS, Torino, Italy
8. Medical Oncology Unit, San Carlo Hospital, Potenza, Italy
9. Department of Oncology, ARNAS Garibaldi, Catania, Italy
10. Department of Oncology, University Hospital, Cagliari, Italy
11. Department of Pathology, University and General Hospital, Udine, Italy
12. Medical Oncology Unit, University Hospital, Parma, Italy