1. Endoscopy Service, Department of Diagnostic and Therapeutic Services, IRCCS – ISMETT (Istituto Mediterraneo per i Trapianti e Terapie ad alta specializzazione), Palermo, Italy
2. Pathology Service, Department of Diagnostic and Therapeutic Services, IRCCS – ISMETT (Istituto Mediterraneo per i Trapianti e Terapie ad alta specializzazione), Palermo, Italy