Expression of cornulin in oral premalignant lesions

Abstract

Objective: The aim of this study was to evaluate expression of cornulin in oral mucosa as an adjunct to histopathologic grading of oral epithelial dysplasia (OED).

Study design: Biomarker expression was assessed in normal oral mucosa, low-grade OED (LD), high-grade OED (HD), and oral squamous cell carcinoma (OSCC) by using immunohistochemistry. Photomicrographs were evaluated with Aperio Imagescope using a positive-pixel-counting algorithm. A histo-score (H-score) was calculated on the basis of staining intensity and the percentage of positive cells (%-staining). Intrarater reliability for H-score and %-staining was determined by calculating interclass correlation coefficients. Mean differences in H-scores and %-percent staining values were each analyzed by using an analysis of variance and Tukey's post hoc procedure.

Results: Cornulin expression progressively diminished with increasing grades of dysplasia and OSCC. Interclass correlation coefficients for H-score and %-staining were each greater than 0.99. Except for OSCC versus HD, all other pairwise comparisons were statistically significant (P < .0001) for H-score and %-staining.

Conclusions: Cornulin expression helped differentiate between low-grade and high-grade oral epithelial dysplasia, making it a potential adjunct for grading oral OEDs and a potential biomarker for risk of lesion progression. Longitudinal studies evaluating risk stratification based on cornulin expression may be warranted.