Absence of Synergistic Effect of Toluidine Blue and Cytomorphometry in Discriminating Dysplasia in Oral Exfoliative Cytology

Numerous tools and techniques such as vital stain, autofluorescence, exfoliative cytology, histomorphometry, etc. were explored in the detection of dysplasia, but have variable sensitivity and specificity. The present study evaluated the effect of toluidine blue in increasing the accuracy of histomorphometry analysis in detection of the dysplasia in OPMDs on exfoliative cytology. An experimental, observational, cross-sectional research was performed on patients attending dental hospitals and in oral health check-up camps suspected of having OPMDs. Cytology smear was collected using the standard protocol before and after the application of a toluidine blue stain over the lesion. Two pathologists performed the dysplasia grading and histomorphometry analysis. Chi-square and t-tests were carried out (p<0.05). The study observed a positive correlation between toluidine blue positivity and dysplasia in OPMDs. The toluidine blue stain sensitivity, specificity, Positive Predictive Value, and Negative predictive value were 39.53 %, 97.56, 97.14, and 43.58% respectively. Toluidine blue before the cytology smear does not improve the diagnostic accuracy of cytomorphometry. Further, there was no significant variation in cellular and nuclear morphometry parameters as compared to normal mucosa. Toluidine blue stain does not improve the efficacy of cytomorphometry in discriminating dysplasia on cytosmears. However, toluidine blue stain can assist clinicians in identifying potential areas of having a suspicion of dysplasia for scalpel biopsy.