Abstract
BACKGROUND/PURPOSE: Salivary gland tumor (SGT) is a rare disease with a largely unknown etiology. The risks of betel quid chewing, alcohol drinking, and cigarette smoking have been well documented in oral cancer but not in SGT. We aimed to investigate the independent and combined effects of betel quid chewing, cigarette smoking, and alcohol consumption on the incidence of SGT. MATERIALS AND METHODS: We conducted a case-control study of 1845 patients aged 35-65 years, including 239 patients with pathologically proven SGT and 1606 controls from the health examination clinics of the same hospital during 2005-2014 to examine the association of these three risk factors with SGT in Taiwan. Adjusted odds ratio (aOR) and their 95% confidence interval for the association of risk factors to SGT were analyzed. RESULTS: After adjusting for covariates, aOR of cigarette smoking, alcohol drinking, and betel quid chewing were 2.50, 1.27, and 3.38, respectively for SGT. The significantly increased risk for SGT was observed in cigarette smoking (P < 0.001). Cigarette smoking was also found to increase risks in subgroups of SGT (aOR = 5.24, 2.41, 2.63, and 2.04 in minor, major, benign, and malignant SGT, respectively). CONCLUSION: Our study provided the first evidence to show the independent and combined impact of betel quid chewing with cigarette smoking and alcohol drinking on the SGT, and support the concept that cigarette smoking may associate with SGT carcinogenesis.