S100 protein-positive dendritic cells and the significance of their density in gastric precancerous lesions.

Quantitative analysis of dendritic cells (DC's) was carried out in tissue specimens of normal gastric mucosa (n = 15), gastric ulcer (n = 19), chronic atrophic gastritis (n = 28), and gastric carcinoma (n = 65) by ABC immunostaining with S100 protein antibody. Significant increases in DC number were observed in chronic atrophic gastritis with type III intestinal metaplasia and/or grade II, III dysplasia. The result suggests that DC's are potentially capable of presenting neoantigens associated with malignant transformation at the precancerous stage when malignant morphological changes have not yet taken place. Combined with routine diagnostic methods, the serial monitoring of DC density in gastric mucosa may be useful in the follow-up of premalignant lesions in the stomach and the diagnosis of early gastric carcinoma.