Smoking cessation is associated with improved survival in oropharynx cancer treated by chemoradiation

Objectives/hypothesis: The effect of smoking and human papillomavirus (HPV) on overall survival (OS) of oropharyngeal squamous cell carcinoma (OPSCC) patients undergoing concurrent chemotherapy (CCRT) remains unclear.

Study design: Retrospective review.

Methods: Clinical characteristics of OPSCC patients treated between 2008 and 2015 with CCRT were abstracted from medical records. OS curves and multivariate cox proportional hazard ratios (HRs) were examined.

Results: Of 120 evaluable patients, 71% had HPV⁺ tumors. Median follow-up duration for the entire cohort was 41.5 months (range = 6-88 months). HPV⁺ current smokers experienced significantly worse 5-year OS (73% alive vs. 36% alive, P = .01) and there was a similar trend in HPV^- current smokers (66% alive vs. 31% alive, P = .28) compared to former/never smokers undergoing CCRT. In a multivariate cox proportional hazard model adjusted for age, gender, and overall tumor stage, HPV⁺ current smokers experienced nearly a fourfold increase in overall mortality in comparison to HPV⁺ never/former smokers (HR = 3.68, 95% CI = 1.35-10.0). Similarly, current smokers with HPV^- tumors (HR = 6.80, 95% CI = 1.11-41.67) had increased mortality compared to never/former smokers.

Conclusions: Current smoking is associated with poor prognosis, independent of HPV status, in CCRT-treated OPSCC patients. Current smoking produced an approximately four- to sevenfold increase in risk of mortality for HPV⁺ and HPV^- patients, respectively. Regardless of pack years and HPV status, efforts should be made to achieve smoking cessation before CCRT.

Level of evidence: 4. Laryngoscope, 126:2733-2738, 2016.