Diagnosis and Management of Dysplasia and Cancer of the Ileal Pouch in Patients With Underlying Inflammatory Bowel Disease

Approximately 30% of the patients with ulcerative colitis (UC) would ultimately require colectomy for medically refractory UC or UC-associated neoplasia. Restorative proctocolectomy with ileal pouch-anal anastomosis has become the surgical treatment of choice for these patients. However, this procedure does not completely abolish the risk for neoplasia of the pouch. The main risk factor for pouch neoplasia is a preoperative diagnosis of UC-associated dysplasia or cancer. Although the natural history and prognosis of pouch dysplasia are not clear, mortality associated with pouch cancer, once diagnosed, appears to be high. Conversely, not all pouch neoplasia follows the chronic inflammation-dysplasia-cancer sequence, which makes pouch endoscopy with biopsy, the current gold standard for surveillance, challenging. In addition, the findings that pouch neoplasia is not common and that pouch endoscopy still misses dysplasia lead to controversy on the need and time interval of routine endoscopic surveillance. However, based on reports in the literature and their own experience, the authors recommend surveillance endoscopy to be performed in patients at risk, such as those with a precolectomy diagnosis of UC-associated neoplasia. This review appraises issues in the prevalence and incidence, risk factors, technical aspects of pouch construction, clinical and pathological features, natural history, surveillance examination, diagnosis, and management of pouch neoplasia. Cancer 2011;117:3081-92. (C) 2017 American Cancer Society