CYTOPATHOLOGY OF THE NASAL-MUCOSA IN SMOKERS - A POSSIBLE BIOMARKER OF AIR-POLLUTION

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 cy tology of the nasal mucosa satisfies these demands. Using brush cytolo gy, 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 cell s were obtained from the maxillo-turbinal region with a small nylon br ush, 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 metapla sia detectable in the remaining 14 of this group. However; in the grou p of cigarette smokers, 52 showed unequivocal dysplasia of various deg rees, whereas merely eight showed only metaplasia. Dividing the smoker s into two groups based on pack/years of cigarette consumption reveale d that the severity of dysplasia (mild or moderate) correlated well wi th the pack/years (P = 0.0001). As yet, no significant relation betwee n smoking habits and the incidence of nasal sinus squamous cell carcin omas 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 cou ld act as a biomarker reflecting similar changes in the lower respirat ory tract.