A Puzzling Case of Pouch Pathology.

A 36-year-old man with familial adenomatous polyposis secondary to an adenomatous polyposis coli mutation status post proctocolectomy with ileal pouch-anal anastomosis presented with hematochezia. Pouchoscopy revealed a 4-cm indurated mass in the distal ileal pouch just 17 months after a normal pouchoscopy. Histopathology was diagnostic for Burkitt lymphoma, and the patient achieved complete remission with subsequent chemotherapy. Although there are reports of Burkitt lymphoma in patients with ileal pouch-anal anastomosis, to date, this is the first report in a patient with familial adenomatous polyposis. This case highlights the presentation of a rapidly enlarging tumor not commonly seen in the adult gastroenterology population.