Laterally spreading tumor-like primary rectal mucosa-associated lymphoid tissue lymphoma: A case report

Ya-Li Wei; Cong-Cong Min; Lin-Lin Ren; Shan Xu; Yun-Qing Chen; Qi Zhang; Wen-Jun Zhao; Cui-Ping Zhang; Xiao-Yan Yin

doi:10.12998/wjcc.v9.i16.3988

Laterally spreading tumor-like primary rectal mucosa-associated lymphoid tissue lymphoma: A case report

World J Clin Cases. 2021 Jun 6;9(16):3988-3995. doi: 10.12998/wjcc.v9.i16.3988.

Authors

Ya-Li Wei¹, Cong-Cong Min¹, Lin-Lin Ren¹, Shan Xu¹, Yun-Qing Chen², Qi Zhang¹, Wen-Jun Zhao¹, Cui-Ping Zhang¹, Xiao-Yan Yin³

Affiliations

¹ Department of Gastroenterology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China.
² Department of Pathology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China.
³ Department of Gastroenterology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China. yxy4503@163.com.

Abstract

Background: Colorectal mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease, and only a few cases have been reported to date. It has no specific clinical presentations and shows various endoscopic appearances. There is no uniform consensus on its treatment. With the advancement of endoscopic technology, endoscopic treatment has achieved better results in individual case reports of early-stage patients.

Case summary: We report a case of rectal MALT in a 57-year-old Chinese man with no symptoms who received endoscopy as part of a routine physical examination, which incidentally found a 25 mm × 20 mm, laterally spreading tumor (LST)-like elevated lesion in the rectum. Therefore, he was referred to our hospital for further endoscopic treatment. Complete and curable removal of the tumor was performed by endoscopic submucosal dissection. We observed enlarged and dilated branch-like vessels similar to those of gastric MALT lymphoma on magnifying endoscopy with narrow-band imaging. And immunopathological staining showed hyperplastic capillaries in the mucosa. Histopathological findings revealed diffusely hyperplastic lymphoid tissue in the lamina propria, with a visible lymphoid follicle structure surrounded by a large number of diffusely infiltrated lymphoid cells that had a relatively simple morphology and clear cytoplasm. In addition, immunohistochemical analysis suggested strongly positive expression for CD20 and Bcl-2. Gene rearrangement results showed positivity for IGH-A, IGH-C, IGK-B, and IGL. Taking all the above findings together, we arrived at a diagnosis of extranodal marginal zone B-cell lymphoma of MALT lymphoma. Positron emission tomography-computed tomography examination showed no other lesions involved. The patient will be followed by periodic endoscopic observation.

Conclusion: In conclusion, we report a case of rectal MALT with an LST-like appearance treated by endoscopic submucosal dissection. Further studies will be needed to explore the clinical behavior, endoscopic appearance, and treatment of rectal MALT.

Keywords: Case report; Endoscopic submucosal dissection; Laterally spreading tumor; Mucosa-associated lymphoid tissue; Primary rectal mucosa-associated lymphoid tissue lymphoma.

Publication types

Case Reports