Characteristics, management of the neck, and oncological outcomes of malignant minor salivary gland tumours in the oral and sinonasal regions.

The aim of this study was to evaluate the characteristics of malignant tumours of the minor salivary glands in the oral and sinonasal regions, to make sure that the neck was managed correctly, and to identify oncological outcomes, retrospectively, at a single hospital. A total of 60 patients were reviewed. Forty-nine patients had intraoral lesions and 11 had sinonasal lesions. Of the 60 patients, 28 had stage I to II malignant tumours, and 32 had stage III to IV tumours. Treatment was almost exclusively surgical. One of the 16 patients whose nodes were clinically clear had an elective neck dissection. Adjuvant radiotherapy was given if indicated. The mean follow-up period was 52 months (range 13-190). Sinonasal lesions were all advanced T-stage at diagnosis, had more invaded resection margins, and a higher local recurrence rate than intraoral lesions. There was no regional recurrence in those patients whose nodes were clinically invaded and who had therapeutic neck dissection, or in the patient whose nodes were clinically clear and who had an elective neck dissection. Occult metastases developed exclusively in adenoid cystic carcinomas (ACC), the rate of which was 4/16. Regional recurrence developed in 4 patients who had never had elective treatment to the neck 2 of whom mixed pattern ACC and 2 who had low grade mucoepidermoid carcinomas (MEC). The overall survival was 90% at 2 years, 77% at 5 years, and 74% at 10 years. Sinonasal minor salivary gland tumours require careful follow-up because resection margins are more likely to be invaded by tumour, and they have a higher local recurrence rate than intraoral lesions. Elective neck dissection is needed, particularly for MEC and also to prevent regional recurrence in ACC.