24142981

PMC4227396

Objectives

Asbestos describes a group of naturally occurring silicate mineral fibers that were widely used in industry during the 20th century due to their desirable physical properties. Although use in the United States has fallen over the last three decades, significant exposure in the developing world continues and the burden of disease is considerable. Asbestos is a known risk factor for several malignant diseases, including lung cancer and mesothelioma, and has more recently been implicated in pharyngeal and laryngeal cancer. However, studies of asbestos and cancers of the larynx or pharynx with adequate sample-size that control for major head and neck squamous cell carcinoma (HNSCC) risk factors remain relatively sparse.

Methods

We report findings from a case-control study of 674 incident male HNSCC cases from the greater Boston region and 857 population-based male controls, matched on age (+/− 3 years), sex, and town or neighborhood of residence. Multivariable logistic regression was used to assess the association between occupational asbestos exposure and HNSCC by primary tumor site.

Results

A total of 190 cases (28.2%) and 203 controls (23.7%) reported an occupational exposure to asbestos. Occupational asbestos exposure was associated with an elevated risk of pharyngeal carcinoma in men (OR = 1.41, 95% CI: 1.01–1.97), adjusted for age, race, smoking, alcohol consumption, education, income, and HPV16 serology, with borderline increasing risk for each decade at the exposed occupation (OR = 1.10, 95% CI: 0.99–1.23).

Conclusion

These observations are consistent with the mounting evidence that asbestos is a risk factor for pharyngeal cancer.

CDC Public Access

K01OH009390/OH/NIOSH CDC HHS/United States
R01 CA078609/CA/NCI NIH HHS/United States
R01 CA100679/CA/NCI NIH HHS/United States
R01 CA121147/CA/NCI NIH HHS/United States
R01CA078609/CA/NCI NIH HHS/United States
R01CA100679/CA/NCI NIH HHS/United States
R01CA121147/CA/NCI NIH HHS/United States
T32 ES007272/ES/NIEHS NIH HHS/United States
T32ES07272/ES/NIEHS NIH HHS/United States