Cytopathology of the Nasal Mucosa in Smokers: A Possible Biomarker of Air Pollution?

Abstract

In our search for an easy, reliable, and inexpensive screening method to assess the toxic effects of air pollution and the attendant cancer risk on the respiratory tract, we investigated to what extent brush cytology of the nasal mucosa satisfies these demands. Using brush cytology, we examined the nasal mucosa of 60 cigarette smokers and compared the cytopathologic findings with those of 60 nonsmokers. All subjects were healthy male office workers with no nasal disorders. Mucosal cells were obtained from the maxillo-turbinal region with a small nylon brush, subsequently processed by Papanicolaou staining on a glass slide, and examined “blinded” by cytopathologists. The cytologic findings were normal in 46 of the nonsmokers, with simple squamous cell metaplasia detectable in the remaining 14 of this group. However, in the group of cigarette smokers, 52 showed unequivocal dysplasia of various degrees, whereas merely eight showed only metaplasia. Dividing the smokers into two groups based on pack/years of cigarette consumption revealed that the severity of dysplasia (mild or moderate) correlated well with the pack/years (P = 0.0001). As yet, no significant relation between smoking habits and the incidence of nasal sinus squamous cell carcinomas has been demonstrated in contrast to the established relationship between smoking and carcinomas of the larynx and lungs. Nevertheless, it is conceivable that cytopathologic changes in the nasal mucosa could act as a biomarker reflecting similar changes in the lower respiratory tract.