AF.129 ENDOSCOPIC SUBMUCOSAL DISSECTION OF LARGE PEDUNCULATED POLYPS WITH WIDE STALKS: EXPERIENCE FROM A SINGLE ITALIAN REFERRAL CENTER. (September 2021) - Fiori, G.; De Roberto, G.; Ravizza, D.; Trovato, C.; Bravi, I.; Giunta, M.; Soru, P.; Crosta, C.