Mo1699 ADVANCED ENDOSCOPIC RESECTION TECHNIQUES FOR LOCAL RECURRENT COLORECTAL ADENOMAS: A SINGLE CENTER PROSPECTIVE STUDY

Local recurrence is a relatively frequent event after endoscopic mucosal resection (EMR), occurring in up to 20% of piecemeal resections. In these cases oncological radicality is mandatory to achieve, but endoscopic re-treatment can be technically challenging due to tissue scar. In this setting, advanced endoscopic resection techniques, such as endoscopic submucosal dissection (ESD) or endoscopic full thickness resection (FTR), could potentially allow en bloc large lesion removal for improved histopathological analysis and higher curative rates. However, to date few data are available on the use of these novel techniques for recurrent adenomas. Thus, the aim of our study was to access the efficacy and safety of ESD and FTR in the setting of post-polipectomy recurrence. We prospectively included all ESD and/or FTR performed for locally recurrent adenomas defined as lesions: 1) reappearing at the site that was previously treated endoscopically, 2) with convergent folds, and 3) with a polypectomy ulcer scar nearby. Data collection included lesions size, location and histology, endoscopic technique (ESD, FTR, hybrid-techniques), early (<48H)/ late complications, and recurrence at 3/6/12-month endoscopic follow-up. From April 2017 to January 2019 11 patients (M/F 5/6, median age 74yrs [IQR 69-80]) were included in the study. Recurrent adenomas had a median size of 17mm [IQR 10-24], being mostly located in the rectum (83%). In total 12 procedures were performed: n.5 ESD (two of which performed with hybrid ESD+EMR), n.6 FTR and hybrid ESD+FTR in one case. At histological examination eight lesions presented tubulovillous architecture, three of which with HGD; n.3 were tubular adenomas with LGD. Recurrence was not confirmed at pathology in one case, which was excluded for efficacy analysis (n.11). No major early/late complications were observed. Only one patient presented post-polypectomy syndrome resolved with medical therapy. 7/11 cases completed endoscopic assessment at 12 months with a median follow-up of 9.8 months [IQR 5-12]. Recurrence was observed in only one case three months after hybrid ESD+EMR; FTR re-treatment was performed with negative endoscopic follow-up at 3 months. In our experience advanced endoscopic techniques (ESD/FTR) performed alone or combined in one session or sequentially represent safe and effective treatment options for locally recurrent adenomas.