Self-reported Tobacco use does not correlate with carcinogen exposure in smokers with head and neck cancer

Objectives/Hypothesis Head and neck squamous cell carcinoma (HNSCC) is strongly associated with tobacco use. We sought to examine the relationship between self-reported tobacco use and the level of urinary tobacco carcinogen metabolites in a cohort of patients with HNSCC. Study Design Cross-sectional analysis. Methods Eighty-four cigarette smokers with head and neck cancer completed tobacco and alcohol use questionnaires, and the following urinary tobacco metabolites were quantified: 1-hydroxypyrene (1-HOP), N'-nitrosonornicotine and its glucuronides (total NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides (total NNAL), and cotinine. A cross-sectional analysis was performed with assessment of correlation coefficients. Results When analyzed based on self-reported cigarettes per day (CPD), no significant correlation with any of the studied tobacco carcinogen metabolites was found. However, urinary cotinine showed significant correlation with total NNN, total NNAL, and 1-HOP. Total NNN, total NNAL, and 1-HOP showed significant correlation with each other suggesting exposure occurs to each proportionally. Conclusions In smokers with HNSCC, self-reported tobacco use does not predict actual carcinogen exposure. In contrast, urinary cotinine levels significantly correlate with carcinogen levels. Therefore, urinary cotinine is the preferred value for estimating carcinogen dose in these patients. 1-HOP levels were significantly associated with total NNN and total NNAL suggesting that smokers are exposed to these carcinogens proportionally. These data indicate that utilizing conventional methods of estimating tobacco exposure (CPD) may not accurately approximate exposure to tobacco carcinogens in smokers with HNSCC. These data have implications for future studies focused on screening and epidemiology of smokers with HNSCC.