![Figure 1.](/tables/gr1068w-g001.jpg)
Figure 1. Endoscopic features of the stomach. Esophagogastroduodenoscopy (EGD) revealed diffuse, nodular, erythematous and ulcerated mucosa in the antrum (a) with narrowing of the pyloric channel (b).
![Figure 2.](/tables/gr1068w-g002.jpg)
Figure 2. Histological features of immunotherapy-associated gastritis and cytomegaloviral (CMV) infection. The antral mucosa showed marked mononuclear inflammatory cell infiltration in the lamina propria (a, hematoxylin & eosin stain (H&E), ×40), crypt apoptosis (b, H&E stain, ×400), apoptotic abscesses (c, H&E stain, ×400), crypt epithelial lymphocytosis (d, H&E stain, ×200) and neutrophilic infiltration in crypt epithelium (e, H&E stain, ×400). Focal erosion and ulceration were noted (f, H&E stain, ×40). In addition, a few prominent lymphoid aggregates were noted in the lamina propria (f, H&E stain, ×40). The glandular epithelium showed regenerative changes (a). No atypia was noted for lymphocytes (d, f). A few cytomegalovirus-infected cells were noted on routine stain (g, H&E stain, ×400) and confirmed by immunohistochemistry (h, immunoperoxidase stain, ×400). Immunohistochemistry for CD3 and CD20 revealed a mixed population of T cells and B cells with T cells primarily in the crypt epithelium and B cells in the lamina propria (i, immunoperoxidase stain, ×200; j, immunoperoxidase stain, ×100).