Adenocarcinoma of the anal transitional zone after double stapled ileal pouch-anal anastomosis for ulcerative colitis.

The development of adenocarcinoma in the anal transitional zone, after restorative proctocolectomy for ulcerative colitis, is rare. We report the first Asian and sixth known case. A 41-year-old Indian lady had a long standing history of ulcerative colitis. Restorative proctocolectomy and stapled ileal pouch-anal anastomosis without mucosectomy was performed. She remained asymptomatic until 3 years later when she complained of discomfort on defecation. A poorly differentiated adenocarcinoma in the anal transition zone was diagnosed and she subsequently underwent an abdomino-perineal resection. The previously reported cases in the literature are reviewed. We also discuss the suggested surveillance for high-risk patients who have undergone an ileal-anal pouch anastomosis.