Tobacco smokers have significantly worse prognosis than do nonsmokers following head and neck squamous cell carcinoma (HNSCC ) diagnoses, despite being younger than nonsmokers, according to a single-institution, retrospective cohort study published in JAMA Otolaryngology-Head & Neck Surgery.
“Smokers were almost twice as likely as nonsmokers to die during the study period,” reported lead study author Nosayaba Osazuwa-Peters, MPH, of the Saint Louis University Cancer Center in St. Louis, Missouri, and coauthors. “We also found that those who were married were less likely to be smokers at diagnosis.”
Recent research has focused on trends related to HPV-positive cancers but smoking “remains as important as oral HPV” as a cause of HNSCC, the authors noted. “Most patients in our study developed primary cancer in subsites that are mostly unrelated to HPV,” they reported.
The study authors analyzed associations between smoking status at HNSCC diagnosis, survival, and marital status using data from the Saint Louis University Hospital Tumor Registry for patients diagnosed between 1997 and 2012. More than half (260 patients; 56.2%) were smokers at diagnosis and 81% were white. Smokers were more likely to also consume alcohol and to be unmarried and younger than 65 years old at diagnosis.
“We found a statistically significant difference in median survival time between smokers (89 months; 95% CI: 65-123 months) and nonsmokers at diagnosis (208 months; 95% CI: 129-235),” the study authors reported. Smokers were “almost twice as likely to die during the study period as nonsmokers” (hazard ratio, 1.98; 95% CI: 1.42-2.77).
In a multivariate analysis, unmarried patients were more likely to smoke (adjusted odds ratio 1.76; 95% CI: 1.08-2.84).
HPV status was not available for the patients and could have modulated the association between smoking and survival because HPV-associated cancers are associated with better survival. Because the analysis was retrospective, smoking and marital status were only known for patients at the time of diagnosis, the authors further cautioned. Changes in either might modulate survival outcomes. Nor were data available to stratify baseline to differentiate former smokers from never-smokers, or to reflect whether former smokers had quit recently or long ago. Smoking status was also self-reported by patients at diagnosis.
The association between smoking and marital status at the time of diagnosis was important because marriage represents “an important component of a patient’s social environment and support,” the authors noted. “Not only is tobacco use a risk factor for HNSCC development, but smoking at diagnosis is associated with decreased survival, increased risk for second primary cancers of the lung, esophagus, and even prostate, hypoxic radioresistance during radiation treatment, as well as increased risk of comorbidities and competing causes of death such as cardiovascular and chronic obstructive pulmonary diseases.”
The findings bolster the case that cancer care should incorporate social support and smoking cessation.