Comparative study of frequency of micronuclei in normal, potentially malignant diseases and oral squamous cell carcinoma

CONTEXT: The assessment of micronuclei (MN) in exfoliated oral epithelial cells is a promising tool for the study of epithelial carcinogens and can be used to detect chromosome breakage or mitotic interference, thought to be relevant to carcinogenesis. AIMS: To detect MN in exfoliated oral mucosal cells in individuals using various tobacco forms and also to detect frequency of MN in premalignant lesions and conditions (potentially malignant diseases [PMD's]) and oral squamous cell carcinoma (OSCC). To correlate frequency of MN in oral exfoliated cells in clinically diagnosed cases of OSCC followed by a histopathological grading. MATERIALS AND METHODS: A total of 90 subjects (30 smokeless tobacco users, 30 smokers and 30 nontobacco users) consisted of clinically diagnosed cases of PMD's and OSCC were selected for the study. Cytosmears from the groups were stained with rapid Papanicolaou stain. MN was identified according to the Tolbert et al. criteria. RESULTS: MN cells were found to be significantly higher in smokeless tobacco users than in smokers. The frequency of MN was three to four times higher in patients with OSCC as compared to patients in PMD's (P < 0.0001). The frequency of MN correlated with the histopathological grade was statistically significant. CONCLUSION: MN index can be used as a biomarker/screening test among the high-risk groups particularly the smokeless tobacco users and PMD's. MN can be a candidate to serve as a biomarker for prediction of the grade of OSCC.