A case of mucosa-associated lymphoid tissue lymphoma of the sigmoid colon presenting as a semipedunculated polyp.
Mucosa-associated lymphoid tissue (MALT) lymphomas are characterized by lymphoepithelial lesions pathologically. Colonic MALT lymphomas are relatively rarer than lymphomas of the stomach or small intestine. Endoscopically, colonic MALT lymphoma frequently appears as a nonpedunculated protruding polypoid mass and/or an ulceration in the cecum and/or rectum. We report a unique case of a colonic MALT lymphoma presenting as a semipedunculated polyp. A 54-year-old man was found to have a 2-cm semipedunculated polyp in the sigmoid colon during screening colonoscopy. The polyp was removed by endoscopic mucosal resection. Histologic examination of the resected polyp revealed diffuse epithelial infiltration by discrete aggregates of lymphoma cells. We diagnosed the tumor as low-grade B-cell MALT lymphoma by immunohistochemical staining.
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Myung Hwan
MH
Kim
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Jin Tae
JT
Jung
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Eui Jung
EJ
Kim
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Tae Won
TW
Kim
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Seon Young
SY
Kim
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Joong Goo
JG
Kwon
Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
Eun Young
EY
Kim
Department of Pathology, Catholic University of Daegu School of Medicine, Daegu, Korea.
Woo Jung
WJ
Sung
Colonic polyps; Mucosa-associated lymphoid tissue lymphoma; Sigmoid colon