Objectives: Adenoid cystic carcinomas (ACC) are rare malignant tumours arising in the major and minor salivary glands. Involvement of the nasal cavity and paranasal sinuses is rare and poorly described. The purpose of this study was to define the clinical and prognostic criteria of ACC of the paranasal sinuses based on the review of a series of 25 cases.

Material and methods: Single-centre retrospective study of 25 cases of ACC of the paranasal sinuses managed between 1998 and 2011, evaluating epidemiological, clinical, diagnostic and prognostic criteria. Factors influencing survival (Kaplan-Meier/Log Rank test) and the patient's quality of life (EORTC QLQ-C30 questionnaire) were also analysed.

Results: Most patients (72%) had a locally-advanced tumour (stage T3 or T4) at diagnosis. Tumour sites, in decreasing order of frequency, were the maxillary sinus, nasal cavities and ethmoid sinus. The most common presenting complaints were maxillary pain or heaviness, unilateral blocked nose, and repeated epistaxis. When the tumour was resectable, treatment comprised a combination of surgery and adjuvant radiotherapy. The 5-year overall survival rate was 63% and the 5-year disease-free survival rate was 43%. The TNM stage at diagnosis (P=0.03), the histological subtype (P=0.023), the possibility of combined surgery and radiotherapy (P=0.03), and local control (P=0.05) were significant factors of improved 5-year overall survival. Positive surgical margins were associated with a trend towards poorer 5-year disease-free survival (ns).

Conclusions: ACC are rare malignant tumours associated with a poor prognosis, characterized by a high recurrence rate. Recommended treatment is a combination of surgery and adjuvant radiotherapy whenever possible. Five-year survival varies as a function of TNM stage, histological subtype, treatment options and local control.