Malignant Salivary Gland Tumours of the Nasal Sinuses and Exophthalmos.

TUMOURS of the ethmoid, maxillary, frontal, and sphenoid air sinuses usually manifest themselves by proptosis. They may take the form of osteoma, chondroma, osteoclastoma, fibroma, myxoma, angioma, psammoma, endothelioma, carcinoma, or sarcoma (Duke-Elder, 1952). The mucous membrane of these sinuses contains not only epithelial and fibro-adenoid layers but also a layer of mucous and serous glands, a part of the accessory salivary glands which are also present in the palate, lips, tongue, gums, tonsillar fossa, pharynx, larynx, trachea, and nose. Such accessory salivary glands may give rise to tumours of the same nature as salivary and lacrimal gland epithelial neoplasms. These may be mixed gland tumours or carcinomata. Mixed gland tumours have also been reported in the eyebrow (Gerlach, 1929), eyelids (Wilson, 1938), and lacrimal sac (McCool, 1939; White, Michaelson, and Heggie, 1938). Tumours developing from the glandular elements of the mucous membrane of the nose and paranasal sinuses constitute only about 10 per cent. of the whole group of mixed salivary tumours (Reese, 1951). Malignant lacrimal or salivary gland tumours may take the form of malignant mixed gland tumour, adeno-carcinoma, or squamous cell, undifferentiated, or adenoid-cystic carcinoma (Hogan and Zimmerman, 1962). Such tumours of the accessory nasal sinuses causing proptosis have been reported so rarely in the ophthalmic literature, that the three following are of great interest.