PMC7522572_01
Endoscopic view of the gastric lesion, showing a round lesion covered with normal appearing mucosa both at high resolution white light (a) and at virtual chromoendoscopy with narrow-band imaging (b), compatible with a sub-epithelial lesion.
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The OGD revealed a centimetric round lesion located at the transition between the gastric fundus and the body, covered with normal appearing mucosa, compatible with a sub-epithelial lesion (Fig. 1).
Endoscopic ultrasonography view of the gastric lesion, showing a round lesion, with definite margins, homogeneously hypoechoic (a) with visible internal vascularization (b), a hard texture at elastography (c), measuring 10 mm x 9 mm. The lesion originated from the submucosal layer (3rd layer) of the stomach with no involvement of the other layers of the gastric wall (a).
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Microscopic examination showed H. pylori-associated chronic gastritis in the antrum and corpus, active, with moderate glandular atrophy and multifocal intestinal metaplasia in the antrum (Fig. 2).
Chronic active gastritis involving the antral mucosa with glandular atrophy and intestinal metaplasia (a) (hematoxylin-eosin, original magnification x20). Giemsa stain shows Helicobacter bacteria closely aderent to the surface of epithelial cells (b) (original magnification x40).
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Tokyo, Japan) which showed a round lesion, with definite margins, homogeneously hypoechoic with visible internal vascularization, a hard texture at elastography, measuring 11 mm x 9 mm. The lesion originated from the submucosal layer (3rd layer) of the stomach with no involvement of the other layers of the gastric wall (Fig. 3).
G-NET with solid-trabecular pattern containing follicular lymphoid aggregates (hematoxylin-eosin, original magnification x20).
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Numerous nodular lymphoid aggregates, some of which with germinal centers, were also seen within the tumor (Fig. 4).
Lymphoid follicular hyperplasia in the mucosa above the tumor (hematoxylin-eosin, original magnification x20).
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The fundic mucosa above the tumor was flattened and contained some lymphoid aggregates with germinal centers located in close proximity to the muscularis mucosae at the base of the lamina propria (Fig. 5).
Immunohistochemical stains for Chromogranin A (a), Synaptophysin (b) and Ki-67 (c).
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Ki67 staining showed a proliferative index of 5% (Fig. 6).