P470 Evolution of asymptomatic unresected lesions in patients operated for multifocal Crohn’s disease

Abstract Background Surgery for Crohn’s disease (CD) aims to treat symptomatic lesions. In multifocal CD, when surgery is required a specific location, should asymptomatic lesions be resected during the same procedure? Methods this retrospective cohort study, all consecutive patients undergoing bowel resection from 2012 2021 CD and which were not (anoperineal excluded) included. Primary endpoint was recurrence on unresected requiring medical treatment intensification or surgery. Univariate analysis of risk factors carried out. Results Among 318 operated 28 (9%) Median evolution duration 9.5 years. Twenty-five (89%) had at least one line 7 (25%) previous CD. Indication complicated (stricture, internal fistula) in 24 (86%) refractory 4 (14%). consisted small 3 (11%), ileocolic 13 (46%) colectomy 12 (43%). The located (25%), colon and/or rectum (43%) both 9 (32%). At 6 months, clinical improvement obtained 18 (64%). After un median follow-up 58.5 step-up, among (31%) targeting treatment. progression-free 43.5 months. Risk associated anoperineal (n=8/10, 80% vs n=5/18, 27.8%, p=0.016) number preoperative lines≥3 (n=7/8, 87.5% n=6/20, 30%, p=0.011). Conclusion most severe allows 65% Although nearly half require adaptations lesions, only 21% these This strategy combining targeted could more widely suggested