Case Report
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jun 6, 2021; 9(16): 3988-3995
Published online Jun 6, 2021. doi: 10.12998/wjcc.v9.i16.3988
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
Ya-Li Wei, Cong-Cong Min, Lin-Lin Ren, Shan Xu, Qi Zhang, Wen-Jun Zhao, Cui-Ping Zhang, Xiao-Yan Yin, Department of Gastroenterology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
Yun-Qing Chen, Department of Pathology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
Author contributions: Wei YL wrote the manuscript; Yin XY performed endoscopic submucosal dissection for the patient and revised the article; Min CC and Ren LL revised the manuscript; Chen YQ contributed to the histopathology and immunohistochemistry staining; all other authors reviewed and approved the final manuscript to be published.
Informed consent statement: Written informed consent from the patient was obtained.
Conflict-of-interest statement: The authors declare that they have no conflict of interest to report.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Xiao-Yan Yin, MD, PhD, Chief Doctor, Department of Gastroenterology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao 266003, Shandong Province, China. yxy4503@163.com
Received: January 2, 2021
Peer-review started: January 2, 2021
First decision: January 27, 2021
Revised: January 31, 2021
Accepted: March 9, 2021
Article in press: March 9, 2021
Published online: June 6, 2021
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: Primary rectal mucosa-associated lymphoid tissue lymphoma, Laterally spreading tumor, Endoscopic submucosal dissection, Mucosa-associated lymphoid tissue, Case report

Core Tip: Compared to mucosa-associated lymphoid tissue (MALT) in the stomach, primary rectal MALT lymphoma remains a rare disease. There are no representative clinical symptoms or endoscopic features reported in the literature. We report a case of rectal MALT lymphoma with a laterally spreading tumor-like appearance. The lesion presented enlarged and dilated vessels on the surface. Endoscopic submucosal dissection was performed. The histopathological and immunohistochemical findings led to a diagnosis of rectal MALT lymphoma.