P535 Outcomes of endoscopic resections of large non-polypoid lesions inflammatory bowel disease: a single United Kingdom centre experience

Abstract

Background: Patients with colitis carry an increased risk for the development of dysplasia. The SCENIC consensus statement recommends endoscopic resection (ER) of all visible dysplasia [1]. Due to technical challenges and limited ER experience in the West of large colitis associated non-polypoid (NP) lesions, such patients are often subjected to colectomy. The King's Institute of Therapeutic Endoscopy (KITE) is a tertiary centre for assessment and ER of challenging colorectal polyps. Here we present the largest single centre case series of large colitis associated NP resections. Methods: Patient demographics, clinical history, lesion characteristics, method of ER and surveillance were collected prospectively in patients undergoing ER of NP lesions 20mm within known distribution of colitis from January 2011 to November 2016. ER techniques included endoscopic mucosal resection, endoscopic submucosal dissection (ESD) and hybrid ESD. Surveillance of resection site with magnification chromendoscopy (mCE) was performed at 3 months (m) with pan colonic mCE at 1-year post ER and annually thereafter. Results: Thirteen lesions satisfied the inclusion criteria in n=13. Patient demographics/clinical data are presented in Table 1. Table 1. Baseline characteristics Mean lesion size was 47.3±22.4 (20–90)mm. All lesions were NP with distinct margins and no ulceration. High frequency mini-probe ultrasound confirmed intramucosal lesions in n=5 where surface pattern was distorted by inflammation. En bloc resection was achieved in n=6. 69% lesions were deeply scarred of which 66% experienced prior instrumentation. ER of 1 lesion was abandoned due to intense fibrosis. Macroscopic evidence of complete ER was achieved in all remaining cases. Endoscopic diagnosis of pre-cancerous lesions of less than 1000μm submucosal invasion was confirmed histologically in 100% of ERs. Complete excision was confirmed in all en bloc resections. A single case of perforation and 1 with delayed minor bleeding were both managed endoscopically. Mortality/hospital admission within 30 days post ER was 0%. Median follow up was 28m (12–35) with no recurrence. Alternative site dysplasia was detected in n=2. All lesions were <20mm and underwent ER. Two patients were referred for colectomy due to a concomitant diagnosis of neuroendocrine tumour and the second with alternate site advanced dysplasia. Conclusions: This case series demonstrates that ER of large colitis associated NP lesions is feasible using an array of methods, safe and has good long term outcomes in a western tertiary endoscopic centre.