Ileal Pouch Cancer Detected More than 30 Years after Restorative Proctocolectomy for Ulcerative Colitis

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INTRODUCTION: The standard surgical treatment for ulcerative colitis (UC) is proctocolectomy with hand-sewn ileoanal pouch anastomosis (hand-sewn IPAA) or stapled ileal pouch anastomosis (stapled IPAA). The occurrence of cancer in the ileal pouch after surgery for UC is rare, and a consensus on surveillance for ileal pouch cancer has not been reached. We report a case of ileal pouch cancer diagnosed by pouchoscopy 33 years after restorative proctocolectomy with IPAA for UC.

CASE PRESENTATION: A middle-aged man presented with positive fecal occult blood. The patient had undergone restorative proctocolectomy with IPAA for UC 33 years ago. Pouchoscopy had been performed every 2–3 years in the last 10 years. In April a year ago, he tested positive for fecal occult blood, and pouchoscopy revealed an ulcerative lesion and flat elevation in the ileal pouch on the proximal side of the ileoanal anastomosis. Targeted biopsies of the ulcerative lesion revealed low-grade dysplasia (LGD). After 4 months, pouchoscopy also showed an increase in the size of the flat elevation, but targeted biopsies of this lesion also showed LGD. One year later in August, endoscopic examination for hematochezia showed a full circumferential raised lesion with a white coat and mucus draining from a fistula near the anastomosis at the same site. Pathological examination identified adenocarcinoma in the ileal mucosa. The preoperative diagnosis was ileal pouch cancer after restorative proctocolectomy with IPAA for UC, cT4bN2M0 stage IIIB (UICC-TNM, 8th), and he underwent excision of the ileal pouch body and the ileoanal anastomosis. Pathological examination showed mucinous carcinoma in the ileal mucosa with chronic inflammation. The postoperative stage was pT3N0M0 stage IIA; no postoperative chemotherapy was administered, and at 6 months postoperatively, the patient remained recurrence free.

CONCLUSION: Although ileal pouch cancer is rare, it can occur after a long period following ileal pouch surgery for UC. Endoscopic surveillance for ileal pouch cancer should be performed for early diagnosis and radical resection, especially if ileal pouch cancer occurs more than 10 years after the onset of UC.