title: Oral tongue squamous cell carcinoma in never-smokers: analysis of clinicopathologic characteristics and survival.
abstract: OBJECTIVE
  (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.
  
  
  METHODS
  Historical cohort study.
  
  
  METHODS
  Academic university medical center.
  
  
  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 χ(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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, California 94115, USA.
authors.forename: Megan L
authors.initials: ML
authors.lastname: Durr
authors.forename: Annemieke
authors.initials: A
authors.lastname: van Zante
authors.forename: David
authors.initials: D
authors.lastname: Li
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Kezirian
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D016022:Case-Control Studies; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012907:Smoking; D015996:Survival Rate; D014062:Tongue Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D055815:Young Adult
keywords: clinicopathologic characteristics; head and neck squamous cell carcinoma; oral cavity carcinoma; survival; tobacco