PMC8077522_01
Preoperative total colonoscopy. a, b Total colonoscopy detected a 20-mm-sized ulcerative mass in the ascending colon (black arrow), and a biopsy specimen from the mass revealed a moderately differentiated adenocarcinoma of the colon.
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F1
Total colonoscopy detected a 20-mm-sized ulcerative mass in the ascending colon (Fig. 1a, b).
Macroscopic findings. The specimen showed a long ulcerative mass with a diameter of 18 mm, a moderately differentiated adenocarcinoma of the colon which invaded the muscularis propria and serosa from the submucosa.
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F2
The specimen was of a moderately differentiated adenocarcinoma of the colon that had invaded the muscularis propria and serosa from the submucosa (Fig. 2).
Microscopic, morphological, and immunohistochemical findings. a A photograph of the specimen (hematoxylin and eosin [H&E] staining, original magnification 40x) shows evidence of a colliding lymphoma (lower) and moderately differentiated adenocarcinoma (upper). b H&E-stain of moderately differentiated adenocarcinoma that invaded the muscularis propria and serosa from the submucosa (original magnification 100x). c H&E-stain of highly diffused proliferation of atypical cells with irregular nuclear-to-cytoplasmic ratio was observed in the adjacent serosa (original magnification 100x); and cytoplasmic immunohistochemical positivity for B-cell marker cluster of differentiation 20 through; d immunochemical staining 20x, and e immunochemical staining 40x, for cluster of differentiation (CD) 20; f immunochemical staining 20x, and g immunochemical staining 40x, for CD79alpha; h immunochemical staining 20x, and i immunochemical staining 40x, for CD 3; j immunochemical staining 20x, and k immunochemical staining 40x, for B-cell lymphoma (Bcl)-2; l immunochemical staining 20x, and m immunochemical staining 40x, for Bcl-6; n immunochemical staining 20x, and o immunochemical staining 40x, for Epstein Barr virus nuclear antigen2.
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F3
Highly diffused proliferation of atypical cells with irregular nuclear-to-cytoplasmic ratio was observed in the adjacent serosa; however, there was no evidence that it had spread to the lymph nodes (Fig. 3a-c). Immunohistochemical analyses showed that the cells were positive for cluster of differentiation (CD)20, CD79alpha, CD3, and B-cell lymphoma (Bcl)-6 and negative for CD10, Bcl-2, and Epstein Barr virus nuclear antigen2 (Fig. 3d-o).