PTU-282 Dysplasia following stapled restorative procto-colectomy for ulcerative colitis: is there a correlation between pre-op colorectal dysplasia and development of post-op dysplasia in the rectal cuff mucosa?

Abstract

Introduction Preserved rectal cuff mucosa following restorative proctocolectomy with ileal-pouch anal anastomosis (RPC-IPAA) in mucosal ulcerative colitis (MUC) carries the risk of malignant transformation and/or recurrent active inflammation (cuffitis). This study aimed to determine: any correlation between pre-op colorectal dysplasia or malignancy and post-op rectal cuff dysplasia; overall risk of post-op dysplasia development in MUC patients after stapled RPC-IPAA; patient compliance with annual rectal cuff biopsies; any potential post-op period during which rectal cuff dysplasia is more prevalent. Method After IRB approval, all MUC patients who underwent stapled RPC-IPAA were identified. Review of demographics, risk factors, operative details and pathology reports (pre- and post-op surveillance biopsies as well as operative specimens) was conducted. Results 611 MUC patients [mean age 46.7 (11–89 years), 368 (60%) males] underwent stapled RPC-IPAA from 1988–2011. Pathology reports were unavailable in 45 and 239 patients had no post-op surveillance biopsies. Among a cohort of 566 patients with obtainable perioperative reports, 16 (2.8%) were histologically diagnosed with “Crohn’s disease (CD)”, 104 (18.4%) with “dysplasia/indefinite for dysplasia without malignancy” and 44 (7.8%) with “adenocarcinoma with or without dysplasia”. Incidental small bowel carcinoid tumours were detected in operative specimens of 6 (1%) patients. 327 patients (58%) had a mean of 8.5 (1–16) identifiable annual post-op rectal cuff biopsies. 282/327 patients (86.2%) had ≤5 post-op surveillance years records available. Post-op rectal cuff dysplasia was identified in 5 patients (1.5%): 2 had no history of dysplasia, 1 had pre-op dysplasia by biopsy, 1 was diagnosed with CD without dysplasia and 1 with adenocarcinoma. One incidence of malignant lymphoma was identified in a post-op pouch surveillance biopsy of a patient who had a previous incidental appendiceal carcinoid. All histologically abnormal post-op surveillance specimens were detected in the first 5 postoperative years. Conclusion The incidence of dysplasia in the rectal cuff after stapled RPC-IPAA in MUC patients was very low (1.5%). There was no correlation between pre-op colorectal dysplasia/malignancy and post-op rectal cuff dysplasia. 327 patients (58%) had a mean of 8.5 (1–16) identifiable annual post-op rectal cuff biopsies. Although no histologically abnormal lesions were detected after 5 post-op surveillance years, 13.8% of patients continued follow up beyond 5 years. Disclosure of interest None Declared.