Validation of cytopathology as a technique for analysis of epithelial cell maturation in oral mucosa of smokers and nonsmokers.

OBJECTIVE: To validate quantitative analysis of epithelial cells in oral mucosa smears of smokers and nonsmokers. STUDY DESIGN: Sixty samples from the oral mucosa of 10 smokers and 10 nonsmokers were collected from the anatomic sites more frequently affected by oral cancer: lower lip, border of the tongue and floor of the mouth. Slides were stained using Papanicolau and Traut techniques; anucleated squamous, nucleated superficial and intermediate cells were counted. RESULTS: The first 50, the first 100 and all nonoverlapping cells on the slide were counted. To compare percentages of cell types, Pearson's correlation coefficient was used. In the first 50 cells analyzed, there was no significant correlation for anucleated cells in lower lip samples of smokers and border of the tongue samples of nonsmokers; for the other types of cells, a significant correlation was found. For the first 100 cells analyzed, all types of cells in the 3 anatomic sites showed a significant correlation, both in smokers and nonsmokers. CONCLUSION: The quantification of the first 100 cells proved to be sufficient to evaluate the epithelial maturation pattern in smears of the lower lip, border of the tongue and floor of the mouth of smokers and nonsmokers.

Assessment of micronucleus frequency in normal oral mucosa of patients exposed to carcinogens.

OBJECTIVE: To assess the presence of micronuclei in exfoliated oral mucosal cells collected from 3 anatomic sites in patients exposed to tobacco and alcohol. STUDY DESIGN: Smears were prepared with normal oral mucosal cells obtained from the lower lip, tongue border and floor of the mouth of 21 controls, 28 tobacco users and 19 tobacco/alcohol users. Slides were stained with Feulgen stain for quantification of micronucleated cells, karyorrhexis and "broken eggs." RESULTS: The groups were similar in terms of the mean number of micronucleated cells and cells undergoing karyorrhexis. In the comparison of anatomic sites, the mean number of cells undergoing karyorrhexis was higher on the lower lip than on the tongue border or floor of the mouth (all groups). A significantly higher number of broken eggs was observed in the control group when compared to the tobacco and tobacco/alcohol groups at all anatomic sites. CONCLUSION: The higher number of broken eggs in patients not exposed to tobacco and/or alcohol suggests that this nuclear alteration may be associated with DNA repair or a healthy mucosa. A trend toward an increased number of micronucleated cells was observed for tobacco and/or alcohol users at all anatomic sites.