P172 Examining dysplasia surveillance in Inflammatory Bowel Disease and Primary Sclerosing Cholangitis - a real world experience.

Seah, D.(1,2);Gow, P.(2,3);Vaughan, R.(1,3);Grace, J.(1,3);De Cruz, P.(1,3);Choy, M.(1,3);

(1)Austin Health, Department of Gastroenterology, Melbourne, Australia;(2)Austin Health, Victorian Liver Transplant Unit, Melbourne, Australia;(3)The University of Melbourne, Department of Medicine, Melbourne, Australia;

Background

Patients with inflammatory bowel disease (IBD) and primary sclerosing cholangitis (PSC) are at high risk of developing colorectal cancer (CRC). Current guidelines recommend annual colonoscopic surveillance immediately following the diagnosis of PSC. This study aimed to assess the surveillance strategy and outcomes in IBD-PSC patients undergoing surveillance for colonic neoplasia (CN).

Methods

We performed a retrospective audit of all patients with IBD-PSC at an IBD and liver transplantation referral centre from 2013–2021, to determine the prevalence and management of dysplasia and CRC and evaluate the adequacy of colonoscopic surveillance. Surveillance was considered up-to-date if colonoscopy was performed at 12 month intervals +/- 3 months.

Results

Ninety-three patients diagnosed with IBD-PSC were identified. Patients who had undergone colectomy prior to enrolment or had colonoscopy performed externally were excluded. Sixty-nine patients were included in the final analysis. Thirty-three percent (23/69) of the cohort developed CN, with an overall rate of dysplasia of 25% (17/69) and CRC in 10% (7/69). Median time to development of CN from IBD diagnosis was 18 years (IQR 10.5-23.75). Only 23% (12/53) of patients were up-to-date with annual colonoscopic surveillance and following detection of neoplasia, chromoendoscopy was utilised in 9% of patients (2/23). 

The rate of CN in patients with up-to-date surveillance was 6/12 (50%), three with low grade dysplasia (LGD) and three indefinite for dysplasia (IND), versus 10/41 (24%, p=0.89) in those without up-to-date surveillance, 6 with LGD, 1 with IND and 2 with CRC. 

Rates of CN were not significantly different between patients who had or had not undergone liver transplantation (18/44 (41%) vs 6/25 (24%), p=0.16). Most patients were managed in Liver Transplant Unit (LTU) clinic (33/69, 48%). Forty-one percent (28/69) were seen in both LTU and IBD clinics, whilst a small number were seen in General Liver clinic (3/69, 4%) and IBD clinic (5/69, 7%) only. The rate of up-to-date surveillance was highest amongst those who were seen in both LTU and IBD clinics (8/28, 29%). In patients with CN, surgery was performed in 46% of cases (11/24): 25% (6/24) underwent sub-total colectomy; whereas, 21% (5/24) underwent segmental colectomy. Two patients developed recurrent dysplasia following segmental colectomy.

Conclusion

In this cohort of IBD-PSC, rates of dysplasia and CRC were high. Adherence to annual colonoscopy surveillance and chromoendoscopy was low. Surgical management of dysplasia or CRC varied. Multidisciplinary coordination between hepatology and IBD specialist services should be implemented to optimise dysplasia surveillance and management.