A Comparative Study of Micronuclei in Oral Exfoliated Epithelial Cells in Potentially Malignant and Oral Squamous Cell Carcinoma

Micronuclei are small, additional nuclei formed as a result of exclusion of chromosome fragments or the whole-chromosome lagging at mitosis. Micronuclei indirectly reflect the chromosomal breakage or impairment of mitotic apparatus. Micronuclei in exfoliated oral epithelial cells are widely used as biomarkers of chromosomal damage, genome instability and cancer risk in humans. Micronuclei scoring can be used as a biomarker to identify different preneoplastic conditions much earlier than manifestations of clinical features and might specifically be exploited in screening of high-risk population for a specific cancer.

To correlate frequency of micronuclei in oral exfoliated cells in clinically diagnosed cases of potentially malignant disorders (PMDs) and oral squamous cell carcinoma.

The study subjects consisted of clinically and histopathologically diagnosed cases of oral squamous cell carcinoma, oral sub mucous fibrosis and leucoplakia. Healthy subjects without any tobacco consumption habits formed the control group. The cytosmear from all the four groups were stained with Papanicolaou stain. Micronuclei were identified according to the criteria given by Tolbert et al. (1992).

The frequency of micronuclei was higher in patients with oral squamous cell carcinoma as compared to the other subject groups and the difference was found to be highly significant.

This study concluded that there is gradual increase in micronuclei counts from normal oral mucosa to PMDs to oral carcinoma.