Tenascin in salivary gland tumours

The distribution of tenascin immunoreactivity was analysed in salivary gland tissue and in various benign and malignant tumours of the salivary gland. In the non-neoplastic tissue, tenascin was seen in the areas of basement membranes of the ductal epithelium. No immunoreactivity could be observed in the serous or mucous glands. In pleomorphic adenomas, tenascin immunoreactivity could be seen in the stromal compartment. It was more pronounced in the dense stromal areas and chondroid elements than in the myxoid area. In Warthin's tumours, strong tenascin immunoreactivity could be observed in the basement membrane zone of the epithelial component. In the lymphatic component, faint reticular staining could be seen. In adenoid cystic carcinomas, acinic cell tumours and mucoepidermoid carcinomas, tenascin showed a linear stromal distribution. No intracytoplasmic immunoreactivity could be seen in any of the cases. The widespread tenascin positivity in salivary gland tumours suggests that tenascin may play a role in the induction and progression of salivary gland tumours, presumably by interfering with the normal parenchymal-mesenchymal interaction.