Basal cell adenocarcinoma of the major salivary glands: A population-level study of 509 cases.

OBJECTIVES/HYPOTHESIS: We sought to better characterize patient, tumor, and long-term survival characteristics of basal cell adenocarcinoma (BCAC) of the major salivary glands with the National Cancer Database (NCDB).

STUDY DESIGN: Retrospective database review of the NCDB (1998-2012).

METHODS: We retrospectively reviewed the NCDB for all cases of major salivary gland BCAC with histologic code 8147/3. Relevant demographic, tumor, and survival variables were extracted and analyzed. COX multivariate regression was performed to identify prognosticators.

RESULTS: Out of 36,224 major salivary gland cancers in the NCDB, we found 509 cases of BCAC (1.4%), 88% of which were in the parotid glands, 11.2% in the submandibular glands, and 0.8% in the sublingual glands. Age at diagnosis ranged from 18 to 92 years (average 64). No gender preference was found (50.7% male). Most tumors were 2 to 4 cm in size (47.3%). Regional (11.9%) and distant metastasis (1.8%) were uncommon. Overall survival at 5 and 10 years was 79% and 62%, respectively. Although numerous variables were found to significantly impact survival on univariate regression analysis, only age ≥ 65 (hazard ratio [HR] 2.55; 95% confidence interval [CI], 1.56-4.19; P < 0.001) and high primary tumor (T)-stage (HR 1.85; 95% CI, 1.16-2.95; P = 0.010) remained significant prognosticators in our multivariate model. For high T-stage disease, surgery with radiation had significantly better survival than surgery alone.

CONCLUSION: Basal cell adenocarcinoma is a rare salivary malignancy with a good prognosis. Regional and distant metastasis were uncommon. Radiation with surgery may help for higher T-stage disease. Old age and high T-stage were significant predictors of worse survival.

LEVEL OF EVIDENCE: 4. Laryngoscope, 126:1086-1090, 2016.