Early Pouchoscopy Is Not Helpful for Surveillance of Dysplasia in the Ileal Pouch

Abstract

BACKGROUND: Pouch surveillance recommendations for dysplasia after ileal pouch anal anastomosis (IPAA) for ulcerative colitis (UC) have yet to be established. The major determinant for developing pouch cancer is dysplasia or carcinoma prior to colectomy. The aim of this study is to describe the findings of our dysplasia surveillance protocol and to examine the yield of early pouchoscopy (6 months) in detecting dysplasia. METHODS: This is a retrospective cohort study based on data collection of patients at the UPR IBD clinics with IPAA for UC that consented to participate in a research protocol approved by the UPR Medical Sciences Campus IRB (#1250200). Current practice in our clinics is to start surveillance pouchoscopy 6 months after the pouch is functional, repeat at 12 months and yearly afterwards. A minimum of 6 biopsies of the ileal pouch and 2 of the cuff are evaluated by experienced pathologists using Riddell's criteria for dysplasia. Data collected includes demographics, medical history and indications for UC surgery, symptoms, pouch function, endoscopic and histologic findings. Of 120 patients identified, 5 were excluded due to development of Crohn's of the pouch, and 8 were excluded due to missing data and biopsy results. The total sample for this study was 107 patients. Variables examined were: age, sex, date of diagnosis, date of colectomy, time of follow up, time of detection of pouchitis, time of detection of cuffitis, and time of detection of dysplasia. Data analysis consisted of descriptive statistics using frequencies, means, standard deviations and incidence rate of dysplasia (SPSS, v23). RESULTS: The study population consisted of 54 males (50.5%) and 53 females (49.5%). The mean age was 37.6 years + 14.5. Nineteen (17.8%) subjects had dysplasia prior to surgery and 3 (2.8%) had colon cancer. Mean follow- up was 87.6 + 60.6 months with a range of 3.2-257.1. Pouch failure occurred in 3 (2.9%), Endoscopic or histologic pouchitis was reported at least once in 93 (88.6%) and cuffitis in 79 (73.8%). Complications included 1 leak, 14 strictures (all successfully dilated), and 1 perianal fistula. Dysplasia in the pouch was reported in 2 patients (1.9%), with a mean time of 47.3 months (range 35-59.6) after surgery. Dysplasia was no longer present on follow-up. Both had dysplasia or carcinoma in situ before colectomy. The incidence rate of dysplasia was 0.0026 per person-year. There was no significant association between pouchitis and dysplasia. CONCLUSION(S): The incidence rate of dysplasia after IPAA in the study population was very low, and first appeared almost 3 years after the surgery. Our results support starting protocol surveillance pouchoscopies after one year of pouch functionality. This will decrease costs and burden to patients without increasing risk of missing the development of dysplasia. We did not analyze studies performed for evaluation of symptoms, as these are outside the scope of the dysplasia surveillance protocol. The impact of the incidental finding of pouchitis in the management and long-term outcome of the patients is also of interest and should be analyzed.