No survival benefit in never-smoker never-drinker patients with oral cavity cancer.

Abstract

Although strongly associated with tobacco and alcohol use, many oral cavity squamous cell carcinoma (OCSCC) cases occur in patients without exposure to either, known as "never-smoker, never-drinkers" (NSND). We aimed to compare clinical outcomes between NSND and tobacco/alcohol-exposed populations and to define demographic characteristics of NSND. We performed a retrospective, single-institution cohort study of 672 OCSCC patients. Cox models were used to estimate differences in overall survival (OS) and recurrence-free survival (RFS) between NSND and tobacco/alcohol-exposed patients while adjusting for confounders. NSND represented 25.6% of our cohort and were older, more female, and more economically advantaged. Among NSND, oral tongue tumors dominated in younger patients, while alveolar ridge tumors dominated in elderly patients. Multivariate survival analysis revealed no differences in OS or RFS between NSND and tobacco/alcohol-exposed patients. When adjusted for independent biologic features, clinical outcomes in OCSCC are similar between NSND and tobacco/alcohol-exposed patients.