Rectal tonsil: a case report and literature review.

The rectal tonsil, a reactive proliferation of lymphoid tissue located in the rectum, is rare. Histologically, benign lymphoid hyperplasia of the rectum is usually characterized by large lymphoid follicles with active germinal centers and a narrow surrounding mantle zone and marginal zone. This lesion is benign, but must be differentiated from the polypoid type of mucosa-associated lymphoid tissue lymphomas. In the current paper, we present a case of rectal tonsil in a 59-year-old woman. We describe the endoscopic ultrasound imaging findings with literature review.