PMC4730741_01
Complete colonoscopy revealed a flat polyp located 35 cm from the anal verge (a). Pathology identified it as an adenomatous polyp. Another 2.0 cm polypoid polyp was found 25 cm from the anal verge (b). It was polypoid with a wide base, slightly irregular border, and an irregular vascular pattern with mild inflammatory changes. We removed the second lesion (shown in b) by endoscopic mucosal resection (c), followed by the application of one hemoclip for wound closure (d)
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Fig1
The polyp was then removed by endoscopic mucosal resection followed by clipping (Fig. 1).
Pathology of the larger polypoid polyp revealed polypoid colonic mucosa with atypical lymphoid cells infiltrating the lamina propria (a). An immunohistochemical study found that the specimen was positive for CD20, CD5, and Bcl-2, and negative for CD10 and cyclin D1, which supported the diagnosis of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue lymphoma type (b). The resected specimen is positive for lymphoma cells, which are present at the cauterized margin (left side of the figure; hematoxylin and eosin stain, 100x) (c)
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Fig2
A pathological examination of the removed polyps identified the smaller polyp as adenomatous and the larger one as a MALT lymphoma, with a polypoid colonic mucosa and atypical lymphoid cells infiltrating the lamina propria (Fig. 2a). An immunohistochemical study demonstrated that the larger polyp was positive for CD20, CD5, and Bcl-2, and negative for CD10 and cyclin D1 (Fig. 2b). However, when reviewed by a pathologist, the margins of the endoscopic mucosal resection specimen were found to be positive (cauterized margin with lymphoma cells; Fig. 2c), although it was free on gross examination.