Keratin proteins identified in epithelial fragments of salivary mucoceles.

Immunohistochemically detected keratin proteins in mucoceles of oral mucosa were used to served as markers to identify epithelial-derived cells of minor salivary glands. Normal ducts of minor salivary glands showed an intense keratin staining. Epithelial lining and or epithelial fragments in cystic walls of mucoceles displayed a strong reaction to keratin proteins too, whereas granulation tissue or connective tissue fibers of the walls were not seen. Foamy macrophages present in cystic cavities signify higher staining with the use of keratin proteins. Mucoceles in oral minor salivary glands are probably caused by ductal obstructions leading to continuous mucous secretion. Keratin proteins were used as an epithelial marker of ductal segments.