Tobacco and alcohol
Tobacco smoking is the most important established risk factor for head and neck cancer. Paradoxically, the prevalence of tobacco smoking among Chinese men is higher at 66% than the prevalence of smoking in other high head and neck cancer incidence countries such as Hungary (44% smoking prevalence; 49.4 head and neck cancer cases per 100,000).
The other main risk factor for head and neck cancer is heavy alcohol drinking. Tobacco and alcohol account for 75 to 90% of the disease in Western countries. Studies show increased risks for smokers on the order of 3 to 4-fold for oral cavity and pharynx cancer, and 10-fold for laryngeal cancer (Vineis 2004). The combined impact of tobacco (cigarettes/day) and alcohol (drinks/week) consumption is greater than the sum of their individual effects and exceeds a multiplicative effect on the risk of head and neck cancers (Hashibe 2009).
Recently we reported on genetic variation in an alcohol metabolism gene (ADH7) to be associated with head and neck cancer risk, but this was specific to the European population (Hashibe 2008). A study in Japan identified SNPs in the ADH4, ADH7 genes that was associated with HNC (Oze 2009).
Human papilloma virus (HPV) is a recognized cause of cancers of the oropharynx and to a lesser extent of the oral cavity (IARC 2007). The level of evidence for the role of HPV in the etiology of laryngeal cancer has been judged to be limited.
The consumption of fruits and vegetables has been associated with decreased risk of head and neck cancers. Other risk factors are specific to subsites within the head and neck. Established risk factors specifically for oral cavity cancer are betel quid and areca nut chewing in India and Taiwan (IARC 2004). Several occupational substances or circumstances such as isopropanol manufacturing, inorganic acid mists containing sulfuric acid and mustard gas are suspected risk factors for laryngeal cancer (Siemiatycki 2004).
Vineis P, Alavanja M, Buffler P, Fontham E, Franceschi S, Gao YT, Gupta PC, Hackshaw A, Matos E, Samet J, Sitas F, Smith J, et al. Tobacco and cancer: recent epidemiological evidence. J Natl Cancer Inst 2004 Jan 21;96(2):99-106.
Hashibe M, McKay JD, Curado MP, Oliveira JC, Koifman S, Koifman R, Zaridze D, Shangina O, Wünsch-Filho V, Eluf-Neto J, et al. Multiple ADH genes are associated with upper aerodigestive cancers. Nat Genet. 2008 Jun;40(6):707-9.
Hashibe M, Brennan P, Chuang SC, Boccia S, Castellsague X, Chen C, Curado MP, Dal Maso L, Daudt AW, Fabianova E, et al. Interaction between tobacco and alcohol use and the risk of head and neck cancer: pooled analysis in the International Head and Neck Cancer Epidemiology Consortium. Cancer Epidemiol Biomarkers Prev. 2009 Feb;18(2):541-50.
IARC monograph: Betel-Quid and Areca-Nut Chewing and Some Related Nitrosamines. IARC Monographs on the Evaluation of the Carcinogenic Risks to Humans 2004;volume 85.
IARC monograph: Human Papillomavirus. IARC Monogr Eval Carcinog Risks Hum 2007;90.
Oze I, Matsuo K, Suzuki T, Kawase T, Watanabe M, Hiraki A, Ito H, Hosono S, Ozawa T, Hatooka S, Yatabe Y, Hasegawa Y, et al. Impact of multiple alcohol dehydrogenase gene polymorphisms on risk of upper aerodigestive tract cancers in a Japanese population. Cancer Epidemiol Biomarkers Prev. 2009 Nov;18(11):3097-102.
Siemiatycki J, Richardson L, Straif K, Latreille B, Lakhani R, Campbell S, Rousseau MC, Boffetta P. Listing occupational carcinogens. Environ Health Perspect 2004 Nov;112(15):1447-59.