Adenocarcinoma below ileoanal anastomosis for ulcerative colitis: Report of a case and review of the literature

BACKGROUND: Restorative proctocolectomy with handsewn ileoanal anastomosis and mucosectomy is warranted in patients with dysplasia and/or cancer on ulcerative colitis to prevent subsequent neoplastic changes in the retained mucosa. However, complete excision of the colonic mucosa cannot be obtained reliably. We report a case of anal canal adenocarcinoma after handsewn anastomosis with mucosectomy. METHODS: A 47-year-old patient, previously submitted to ileorectal anastomosis for colonic cancer on ulcerative colitis, underwent completion proctectomy and handsewn ileoanal anastomosis with mucosectomy for recurrent anastomotic cancer. Two years later, we submitted the patient to pouch removal with permanent ileostomy for a mucinous adenocarcinoma of the anal canal (T2N2Mx) found at follow-up pouch endoscopy. CONCLUSIONS: Only four cases of adenocarcinoma after handsewn anastomosis have been reported in the literature. This new case we report confirms that the risk of malignancy after ileoanal anastomosis with mucosectomy, although small, is real, despite the surgeon taking care with this particular step of the procedure. Careful surveillance is needed in patients with surgical treatment for long-term ulcerative colitis or dysplasia.