PTH-070 Endoscopic Resection of Giant, (> 4Cm) Sessile/Flat Colonic Polyps: Techniques and outcomes

Introduction Giant, sessile/flat colon polyps (> 4cm) are challenging to remove endoscopically and many lesions are still treated with laparoscopic or open segmental resection. Methods From our prospective, tertiary referral, polypectomy database of large colorectal polyps, 107/297 consecutive patients with 109/316 colon polyps, were referred for endoscopic resection of > 4cm flat/sessile colon polyps with a mean size (± SD), 52 ± 22mm. Reasons for tertiary referrals were large polyp size/extent with moderate to severe submucosal fibrosis (SF) (37%), difficult endoscopic access (36%) or failure to adequately lift (24%). Polyps were assessed and treated using ‘inject and cut’ piecemeal Endoscopic Mucosal Resection (P-EMR) or P-EMR with Endoscopic Mucosal Ablation (P-EMR/EMA). Supplementary techniques such as Endocuff-assisted polypectomy (EAP) and Laparoscopic-assisted endoscopic polypectomy (LAP) were employed to improve endoscopic access. Completion rates, recurrence, and adverse events were documented prospectively. Results Nineteen P-EMR/EMA hybrids, 29 Spiral snare (Olympus) P-EMR’s and 2 EAP’s were performed to treat polyps with SF (42% previously failed polypectomy attempt at referring centre, 7.5% tattoo under polyp and 51.5% lesion-related fibrosis) and improve endoscopic access. Polypectomy was considered successful in 94.5% in a single session with mean procedure time (± SD), 43 ± 12.2 min. One deep submucosal tear (0.9%) was successfully treated with endoclips. Eight patients (7.4%) required hospitalisation due to delayed post-polypectomy bleeding with one undergoing emergency laparotomy. There was no mortality. First follow up (3/6 months) was attended by 92/107 patients with no recurrence in 41/92 (3 malignant polyps favourable histology), easily treatable benign recurrence of < 10mm in 39/92 and > 10mm recurrence in 12/92 (one patient with large rectal recurrence had a TEMS procedure and two patients with histology showing malignancy had segmental resections). A second f/u (9/15 months post initial resection) was performed in 40/92 patients with no recurrence in 28/40, < 10 mm benign recurrence in 11/42 (continuing surveillance) and one benign recurrence > 10mm (continuing surveillance). Conclusion Endoscopic resection of giant, > 4cm, sessile/flat colon polyps demands a multi-modality approach, but good medium term outcomes can be achieved with most patients spared surgery. Minor recurrence occurs frequently but can be successfully managed with close surveillance. Disclosure of Interest None Declared.