Malignant tumours of the minor salivary glands--a 20 year review.

The UK incidence of malignant disease of the minor salivary glands is only 0.6 per million per year. The tumours have a varied histology, can present in any age group and are frequently advanced if located in the sinonasal cavities. In a 20-year review of 21 patients treated for minor salivary gland malignancy in a single institution, it was found that mucoepidermoid tumours were more common in the oral cavity and adenoid cystic carcinomas in the sinonasal tract (p = 0.002). Outcome was variable with sinonasal and adenoid cystic carcinoma having a poorer outcome. Kaplan-Meier curves showed that oral tumours had a higher probability of long term survival. Radical surgery with reconstruction and post-operative adjuvant radiotherapy was effective in achieving loco-regional control. There were no local recurrences within 5 years and three after 5 years. Five patients developed metastatic disease within 10 years and a further two after 10 years. Late recurrences occurred and survival was mainly determined by the presence of systemic disease.