A case of mucoepidermoid carcinoma with calcified bodies in the stroma which appeared in a 24-year-old woman was studied ultrastructurally and electron-microanalytically. In this neoplasm, two types of abnormal epithelial secretions-flowing out type and basal secretion type-were observed. Calcified round bodies were noticed in the stromal tissues of this neoplasm. We discussed the relationship between the abnormal epithelial secretion into the stromal tissues and this calcification.
