Adenoid Cystic Carcinoma of the Head and Neck

Adenoid cystic carcinoma (ACC) is a rare malignant tumour believed to arise from the epithelial cells of mucous-secreting glands. It is a slow-growing but aggressive tumour with a propensity for perineural invasion. A 10 year review of 45 patients (19 males and 26 females with a median age of 56 years) treated for ACC at a single institution between 1989 and 1999 was performed to analyse factors involved in treatment failure, local control, treatment-related morbidity and mortality. The data collected were treated for survival curves according to the Kaplan-Meier method and the log-rank test was used to assess the statistical significance of the various groups. The overall survivals at 3 years and 5 years were 71% and 65%, respectively, while the disease-free survivals at 3 years and 5 years were 73% and 63% respectively. Out of the 45 patients, only six had local recurrences, yielding an 87% locoregional freedom from relapse; 16 patients (35.6%) developed distant metastases, with the lung (8/16) being the commonest site. Patients treated for tumours of the nose and paranasal sinuses experienced more morbidity than those with tumours at other sites. Positive margins, perineural invasion and solid histology of ACC were associated with increased morbidity and treatment failure. Patients treated with combined therapy did better than those who underwent a single treatment modality.