Immunohistochemical analysis of a case of gastritis cystica profunda associated with carcinoma development.

We report a rare case of gastritis cystica profunda (GCP) accompanied by carcinoma that developed in a 51-year-old Japanese man without antecedent gastric surgery. The polypoid tumor was located in the upper body of the resected stomach. Histologically, it was characterized by herniation of surface epithelium and cystic glands in the submucosa, muscularis propria, and subserosa. Marked chronic atrophic gastritis was found throughout the stomach, and dysplastic epithelia and a few adenocarcinoma cells were found in the deeper parts of the GCP. The Ki-67, p53, and p21WAF1/CIP1 labeling indices for the deeper part of the GCP were higher than those for the superficial parts or the surrounding mucosa, suggesting that both epithelial cell proliferation and p53-dependent p21WAF1/CIP1 expression in DNA-damaged cells, which might be associated with gastritis, are enhanced in line with penetration of glands. The underlying mechanisms might be linked in a chain of factors leading to malignancy.