NATURALLY-OCCURRING MUCOEPIDERMOID CARCINOMA IN THE SUBMANDIBULAR SALIVARY-GLAND OF 2 MICE

Mucoepidermoid carcinomas in two mice were investigated histologically , immunohistochemically and ultrastructurally. The neoplastic cells sh owed divergent differentiation into periodic acid-Schiff-positive muco us cells, keratin-positive squamous cells, and cells with both mucous granules and sheaves of tonofilaments. Gland formation and keratinizat ion were not observed. At the periphery of tumour cell nests, some cel ls were immunolabelled for smooth muscle actin or contained concentrat ed thin filaments, and these observations were interpreted to indicate that murine mucoepidermoid carcinomas are associated with both myoepi thelium and duct epithelium. (C) 1998 W.B. Saunders Company Limited.