Abstract

MALT (mucosa-associated lymphoid tissue) lymphomas are the most common primary gastrointestinal (GI) lymphomas. MALT lymphomas of the GI tract tend to occur most commonly in the stomach, followed by the small intestine, ileocecal area, colon and the esophagus. However, MALT lymphomas of the large intestine are rare. Previously, a diagnosis was commonly established by the surgical specimens but endoscopic biopsy specimens are currently used to make a diagnosis. A 61-year-old woman was found to have multiple submucosal tumors of the rectum during a screening colonoscopy. The tumors were removed by a polypectomy. The histology revealed the diffuse infiltration of centrocyte-like cells and a lymphoepithelial lesion. Immunohistochemical staining confirmed the diagnosis of a low grade B cell lymphoma of the MALT type. No other site of involvement was identified on the CT of the chest, abdomen and pelvis. (Korean J Gastrointest Endosc 2007;35:272-276)

• Keywords: Lymphoma, Mucosa-associated lymphoid tissue, Rectum