Adenocarcinoma in Ileal Pouch-Anal Anastomosis: The Cleveland Clinic Experience

Abstract

Purpose: Total proctocolectomy with ileal pouch-anal anastomosis substantially reduces the risk for dysplasia and cancer associated with ulcerative colitis (UC). Cancer in ileal pouch-anal anastmosis (IPAA) patients with underlying UC is a rare, which has only been reported as single cases. Natural history of IPAA cancer in these patients and its risk factors have not been investigated and there is lack of consensus for endoscopic cancer surveillance for these patients. The aim of the study was to characterize the natural history and clinical features, and histology in a group of patients with cancer of IPAA. Methods: Pouch database of 2,750 cases was searched. All patients had a preoperative diagnosis of UC or indeterminate colitis. Patients with cancer from the pouch and/or anal transitional zone (ATZ) were identified. Clinical features of these patients were characterized. Results: Eight patients (0.29%) with adenocarcinoma of the pouch and/or ATZ were identified from the database. Average age at cancer diagnosis was 56.8 ± 12.5 (SD) years. The mean duration from IBD diagnosis to cancer and from ileostomy take-down after IPAA to cancer diagnosis was 22.8 and 8.7 years, respectively. Most [5/8(62.5%)] had regular pouch endoscopic-surveillance after IPAA. Six cases had ATZ cancers and 2 had cancers of the pouch. Conclusion: The risk for cancer of IPAA is small but real, which can occur in UC patients without pre-colectomy diagnosis of dysplasia or cancer. A disproportional high number of these patients had post-operative Crohn's disease of the pouch. The majority of the patients had histologic poorly-differentiated cancer. Mucosectomy does not necessarily prevent cancers of the ATZ or pouch.Table: Demographic and Clinical Features of the 8 Patients with Cancer of IPAA