Oral Tongue Squamous Cell Carcinoma in Never-Smokers: Analysis of Clinicopathologic Characteristics and Survival

Objectives (1) To compare clinical characteristics, survival, and recurrence between never-smokers and ever-smokers with oral tongue squamous cell carcinoma (OTSCC). (2) To assess the relationship between clinicopathologic characteristics and survival/recurrence in OTSCC. Study Design Historical cohort study. Setting Academic university medical center. Subjects and Methods This is a study of 120 patients with OTSCC who were treated from January 1999 to February 2010. Clinicopathologic factors were compared between never-smokers and ever-smokers using t tests and (2) tests. Cox regression analyses examined their association with survival and recurrence. Results Of 120 subjects, 66 (55%) were prior or current smokers. There were no significant differences in clinicopathologic factors between ever-smokers and never-smokers. After adjustment for clinicopathologic factors, multivariate Cox regression analysis demonstrated decreased overall survival for never-smokers, but this difference was not significant (hazard ratio [HR], 2.84; P = .056). Increased depth of tumor invasion (HR per millimter invasion, 1.09; P = .005), nodal metastasis (HR, 7.1; P = .025), and stage III or IV disease (HR, 9.45 and 7.31; P = .026 and .029, respectively) were associated with decreased overall survival. Perineural invasion (HR, 8.56; P = .005) and lymphovascular invasion (HR, 6.01; P = .011) were associated with disease recurrence. Conclusion Overall survival may be decreased in never-smokers with OTSCC. Greater depth of tumor invasion and more advanced stage disease are associated with decreased survival. Perineural invasion and lymphovascular invasion are associated with disease recurrence.