Immunohistochemical analysis of CagA expression in the tumor cells of gastric DLBCL. (A) Endoscopy showing multiple irregular ulcerative masses in the cardia of the stomach of an 86-year-old woman. Right bottom inset, Endoscopic ultrasonography shows a homogenous hypoechoic mass infiltration of mucosa and submucosa (white arrow, maximal thickness [7 mm]) of the gastric wall. (B) Six months after completion of HPE, complete remission (CR) was achieved. (C) Tumor cell nuclear CagA expression in the same case; original magnification ×400. (D) Cytoplasmic expression of BCL10 in tumor cells of the same case; original magnification ×400. (E) Cytoplasmic expression of NF-κB in tumor cells of the same case; original magnification ×400. (F) No CagA expression in specimens of gastritis (6 months after completion of HPE) in the same case; original magnification ×400. (G) An HP-dependent gastric “pure” DLBCL case (time to CR after completion of HPE, 1 month) displaying nuclear CagA expression in the tumor cells of the gastric mucosa; original magnification ×400. (H) An HP-dependent gastric DLBCL(MALT) case (time to CR after completion of HPE, 3 month) displaying nuclear CagA expression in the tumor cells of the gastric mucosa; original magnification ×400.