Aggrandizing oral submucous fibrosis grading using an adjunct special stain: A pilot study

INTRODUCTION: Oral submucous fibrosis (OSMF) is graded according to various histological factors which include the epithelial changes and the connective tissue changes. These features though could be identified in routine hematoxylin and eosin (H and E) staining; they could be better appreciated in special stains. This pilot study is an attempt to identify a single special stain that can act as an adjunct to H and E stain to help grade this potentially malignant disease. AIMS AND OBJECTIVES: To assess if special stains can improvise on differentiating the various histological changes seen in OSMF and to accordingly grade OSMF cases. MATERIALS AND METHODS: Formalin-fixed paraffin-embedded tissue sections of OSMF-10 cases of each grade (n = 30). Three special stains: Van-Gieson, Mallory's trichrome and Masson trichrome. STATISTICAL ANALYSIS: The results obtained were tabulated and statistically analyzed using Chi-square test. OBSERVATIONS AND RESULTS: The thickness and degree of keratinization were best detected in Mallory's stain (100%) and were statistically significant; the subepithelial changes were better detected using special stains, especially Mallory's stain (100%). The changes in collagen fibers were better visualized in all three special stains but were not statistically significant. The changes in blood vessels were better detected in Van-Gieson's and Mallory's stain; the obtained results were statistically significant. The degree of fibrosis between muscle bundles could be detected in all the three special stains, but when compared the results were not statistically significant. The questionable areas of muscle degeneration, especially in deeper connective tissue were better detected in Mallory's (43%) and Masson's stain (43%) as compared to Van-Gieson stain (14%) and the results obtained were statistically significant. The inflammatory cells and dysplastic features are better visualized in routine H and E stains. CONCLUSION: Pathogenesis of OSMF is related to fibro-elastic and muscle degenerative changes in the connective tissue followed by secondary changes in epithelium. Routine H and E, stains all the connective tissue components in various shades of pink, use of special stains bestows contrast between different components of connective tissue, thus improvising grading of OSMF. Mallory's stain can be used as a single adjunct to H and E stain as both pattern of keratinization in the epithelium and changes in the superficial and deeper connective tissue could be ascertained.