Ulcerative Colitis-Associated Neoplasia.

A 58-year-old man with a 20-year history of ulcerative colitis (UC) presented with partial large bowel obstruction, and colonoscopy demonstrated a partial obstructing splenic flexure mass, with the remaining colorectum showing quiescent colitis. His colitis was well controlled with ustekinumab, and his last colonoscopy was normal 2-years prior. Staging revealed no metastatic disease, and his carcinoembryonic antigen (CEA) was 2.0 ng/mL. A laparoscopic total abdominal colectomy with end ileostomy was performed. Pathology revealed pT3N0 colonic adenocarcinoma with several high-risk features (obstruction and microscopic lymphovascular invasion), and adjuvant chemotherapy was recommended. The patient was eager to undergo ileal pouch-anal anastomosis (IPAA). An examination under anesthesia (EUA) with multiple biopsies of the future rectal cuff was scheduled 1 month after completing chemotherapy.