Elevated levels of 1-hydroxypyrene and N′-nitrosonornicotine in smokers with head and neck cancer: A matched control study

Background Head and neck squamous cell carcinoma (HNSCC) is associated with tobacco use. Still, most smokers do not develop HNSCC. The mechanisms of varying susceptibility to HNSCC are poorly studied to date. Tobacco metabolite research provides insight regarding the innate metabolism and excretion of carcinogens. Methods Smokers with HNSCC (cases) were compared with smokers without HNSCC (controls) in a matched cohort. The tobacco metabolites studied were: 1-hydroxypyrene (1-HOP), N′-nitrosonornicotine (NNN), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). Results In 33 subjects, mean 1-HOP was 1.82 pmol/mg creatinine versus 1.08 pmol/mg creatinine (p =.004) and mean NNN was 0.10 pmol/mg creatinine versus 0.04 pmol/mg creatinine (p =.01) in cases and controls, respectively. NNAL did not differ between groups. Conclusions Smokers with HNSCC have elevated urinary levels of 1-HOP and total NNN compared with matched controls, suggesting an increased effective exposure to these carcinogens. Tobacco constituent metabolites may be useful in understanding tobacco-related carcinogenesis in HNSCC.