Adenoid cystic carcinoma of the sinonasal tract: a review of the national cancer database.

BACKGROUND: Sinonasal adenoid cystic carcinoma (SNACC) is a rare malignancy with a propensity for distant metastasis. In this study we describe the incidence and determinants of survival among patients with SNACC between the years 2004 and 2012 using the National Cancer Database (NCDB).

METHODS: This was a retrospective, population-based cohort study performed at a tertiary academic medical center. All participants were diagnosed with SNACC between 2004 and 2012 within the NCDB. The main outcome was overall survival (OS).

RESULTS: A total of 793 patients were identified. The cohort was composed of 46.9% males. Mean age at diagnosis was 59.6 years. The maxillary sinus was the most common primary site (49.7%). Nodal disease was seen in 3.6% of the patients, whereas 3.7% had distant metastases. Stage IV disease was seen in 49.1% of cases. In total, 77.4% of patients underwent surgery, 68.2% received radiation therapy, and 16.4% had chemotherapy. Median OS was 78.5 months; OS at 1, 2, and 5 years was 91%, 83%, and 61%, respectively. On multivariate analysis, advanced age (p = 0.001), frontal sinus primary site (p < 0.001), positive margins (p < 0.001), Charlson comorbidity index >0 (p = 0.01), residing in an urban setting (p = 0.04), poorly differentiated or undifferentiated tumor grade (p = 0.003), and advanced tumor stage (p = 0.01) were associated with worse OS, whereas surgery (p < 0.001), but not radiation therapy (p = 0.52) or chemotherapy (p = 0.57), predicted improved OS.

CONCLUSION: Predictors of survival in SNACC include age, comorbidity status, grade, and stage. Surgery is associated with improved survival and remains the mainstay of therapy, whereas the roles of radiation therapy and chemotherapy require future investigation.