Management of Ileal Pouch Cancer in Patients With Inflammatory Bowel Disease.

Background and aims: Ileal pouch cancer in patients with inflammatory bowel disease, though rare, represents a significant concern due to the high mortality. While prior studies emphasized incidence and risk factors, this study evaluates the current management and prognosis of pouch cancer following ileal pouch-anal anastomosis. Methods: Consecutive patients with pouch cancer were identified from a prospectively maintained database (2019-2025). Patients with familial adenomatous polyposis and precancerous conditions were excluded. Demographic, clinical, endoscopic, and histologic data were collected. Primary outcomes were disease recurrence/progression and oncological survival. Results: Of 699 patients, 10 developed pouch cancer (incidence: 0.5 per 100 person-years). Lesions were located at the cuff (n = 3), anal transition zone (n = 3), pouch body (n = 2), prepouch ileum (n = 1), and both anal transition zone and pouch body (n = 1). Two patients presented with distant metastases without endoscopically visible lesions in the pouch. The histological types were adenocarcinoma (n = 5), squamous cell carcinoma (n = 3), non-Hodgkin lymphoma (n = 1), and neuroendocrine tumor (n = 1). The diagnosis was established through endoscopic biopsies (n = 2), surgical resection (n = 6; three with prior endoscopically diagnosed dysplasia), and cross-sectional imaging (n = 2). Seven patients had localized disease, allowing curative treatment. Treatments included surgery (n = 5), chemoradiotherapy (n = 6), and lanreotide for neuroendocrine tumor. Over a median follow-up of 2.8 years (interquartile range: 1.5-5.2), recurrence or disease progression occurred in three patients (30%), and one patient (10%) died from pouch cancer, with a 5-year cumulative survival of 88.9%. Conclusion: Adenocarcinoma remains the most common histological type; however, nonadenocarcinoma, especially the squamous cell carcinoma, has been increasingly recognized. Endoscopic surveillance was helpful in detecting precancerous lesions.