1 National Institute of Gastroenterology, IRCCS- Saverio de Bellis Research Hospital, Via Turi 27, 70013, Castellana Grotte, Italy.
2 Institute of Pathology, University of Regensburg, 93053, Regensburg, Germany.
3 Institute of Pathology, University of Greifswald, 17489, Greifswald, Germany.
4 National Institute of Gastroenterology, IRCCS- Saverio de Bellis Research Hospital, Via Turi 27, 70013, Castellana Grotte, Italy. gianluigi.giannelli@irccsdebellis.it.