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 x2 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 millimeter 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 neversmokers 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.