A Puzzling Case of Pouch Pathology

Abstract

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.

Figure 1.

Endoscopic image of an infiltrating mass found at the distal ileal pouch during pouchoscopy.

Figure 2.

Histopathology demonstrating a diffuse infiltrate of neoplastic lymphoid cells arranged in sheets and cords in a background of necrotic debris. The neoplastic lymphoid cells are large with irregular nuclear contours, open chromatin, and distinct nucleoli. Frequent apoptotic bodies and occasional mitotic figures are present.