HISTOPATHOLOGICAL GRADING OF ORAL SQUAMOUS CELL CARCINOMA BY MICRONUCLEI ASSAY, A POTENTIAL BIOMARKER IN ORAL EXFOLIATED CELLS

Abstract

Background: Micronucleus is a microscopically visible round or oval cytoplasmic chromatin mass in the extra nuclear vicinity, originated from aberrant mitosis, which consists of eccentric chromosomes that have failed to reach spindle poles during mitosis and are used as biomarkers for assessment of DNA damage. Micronuclei in exfoliated oral epithelial cells have been shown in some studies to correlate with severity of this genotoxic damage. This severity can be measured in terms of grading of the lesions. Aim: To correlate frequency of micronuclei (MN) in oral exfoliated cells in clinically diagnosed cases of oral squamous cell carcinoma (OSCC) followed by a histopathological grading. Materials and Methods : The study subjects consisted of clinically diagnosed cases of OSCC. Healthy subjects without any tobacco consumption habits formed the control group.The cytosmears from both groups were stained with rapid Papanicolaou stain. MN were identified according to the criteria given by Tolbert et al. Results: The frequency of MN was three to four times higher in patients with OSCC as compared to patients in the control group and the difference was found to be highly significant. In 75% cases, the cytological grade as determined by the frequency of micronuclei correlated with the histopathological grade and this observation was statistically significant. Conclusions : The MN is potentially an excellent candidate to serve as such a biomarker for prediction of the grade of OSCC.