Adenoid cystic carcinoma of head and neck: A single institutional analysis of 66 patients treated with multi-modality approach

BACKGROUND: Adenoid cystic carcinoma (ACC) accounts for 1% of all head and neck (HN) cancers. MATERIALS AND METHODS: Demographic, clinical, treatment, and survival details of 66 patients were collected (1995-2011) and analyzed. Disease-free survival (DFS) was estimated by Kaplan-Meier method. RESULTS: Primary disease sites were sinonasal (n = 27), salivary gland (n = 30), and others (n = 9). Median follow-up was 23 months (range: 12-211 months). Estimated DFS at 2- and 5-year were 75% and 67.2%, respectively. On univariate analysis, intra-cranial extension (ICE) (hazard ratio [HR]: 3.59, P = 0.0071), lymph node involvement (HR: 4.05, P = 0.0065), treatment modality (others vs. surgery plus adjuvant radiotherapy, HR: 2.39, P = 0.0286) and T stage (T3/4 vs. T1/2, HR: 3.27, P = 0.007) had significant impact on DFS. Lymph node involvement (P = 0.038) and ICE (P = 0.038) continued to have significant impact on DFS on multivariate analysis. CONCLUSION: Surgery followed by adjuvant radiotherapy remains the treatment of choice for HN ACC. Lymph node involvement and ICE confer poor prognosis.