Influence of smoking and alcohol drinking behaviors on treatment outcomes of patients with squamous cell carcinomas of the head and neck.

PURPOSE: To retrospectively evaluate the prognostic value of smoking and drinking status in patients with head-and-neck squamous cell carcinomas. METHODS AND MATERIALS: All patients with all stages and sites were included if complete information was available on baseline smoking and alcohol behavior (never, former, active), disease stage, primary site, radiation dose, sex, and age. Treatment was radiotherapy in 973 patients, postoperative radiotherapy in 469, and chemoradiotherapy in 429. Statistical analysis was performed with Kaplan-Meier and Cox methods.
RESULTS: Data from 1,871 patients were available. At baseline, 9% of patients never smoked, 40% were former smokers, and 51% were active smokers; 20% never drank, 25% were former drinkers, and 55% were active drinkers. Smoking was associated with inferior local control and survival. For local control, the hazard ratio (HR) of active smokers vs. former smokers was 1.5 (p = 0.0001). For survival, the HRs of former smokers and active smokers vs. those who never smoked were also statistically significant (1.3 and 1.7, respectively, p = 0.000001). Alcohol drinking was associated with local control (p = 0.03), and was associated with survival. For survival, HRs of former and active drinkers compared with those who never drank were, respectively, 1.1 (p = 0.01) and 1.28 (p = 0.001). Adjusted 5-year local control and survival rates for those who never smoked and never drank were 87% and 77%, respectively, and for those who were both active smokers and active drinkers were 72% (p = 0.007) and 52% (p = 0.0009), respectively.
CONCLUSION: Smoking and drinking at baseline were associated with poor outcomes in these patients.