Conventional, NBI-magnification endoscopic and endocytoscopic appearances and histopathological and immunohistological findings in Case 3 of MALT lymphoma of the stomach. Conventional gastroscopy shows slightly depressed, discolored mucosa with granularity seen on the anterior wall of the middle gastric body (A). Magnified endoscopic examination with NBI reveals irregular microsurface structures including dilatation or ballooning and destruction of gastric pits (B) and non-structural mucosa devoid of pits (C) and alterations in microvascular architectures with elongation and distortion (C). Endocytoscopy reveals that the epithelial architectures are infiltrated by dense cellular elements, characterized by smaller-sized and intensely stained nuclei compared to the columnar epithelia (D). The intervening uninvolved mucosa shows nominal irregularity with small round or oval pits and scattered cellular infiltrate between the pits (E). Histopathological examination of target biopsies shows dense diffuse infiltrate of centrocyte-like cells in the lamina propriae and the presence of lymphoepithelial lesions (F, hematoxylin and eosin staining, magnification, X200). The neoplastic cells show prominent immunoreactivity to CD79a (G, magnification, X200) on immunohistochemistry. After achievement of complete regression (CR), the endocytoscopic findings have returned to be basically normal with small round or oval pits and scattered cellular infiltrate between the pits, similar to those seen in the surrounding uninvolved mucosa (H).