Development of invasive adenocarcinoma in a long-standing diverted ileal J-pouch for ulcerative colitis: report of a case.

We report a case of a 50-year-old male with ulcerative colitis who developed well-differentiated adenocarcinoma in the ileal J-pouch, which had been defunctioning for 18 years. The extension of the carcinoma in the pouch suggested that it had recently appeared in the pouch. Monitoring by endoscopic examination and biopsy or pouch excision seems to be an appropriate action if a pouch is out of the fecal stream.