Comparing modified papanicolaou stain with ayoub-shklar and haematoxylin-eosin stain for demonstration of keratin in paraffin embedded tissue sections

AIM: The aim of the present study was to stain the known keratin containing tissues by Haematoxylin and eosin stain (H-E), ayoub-shklar (A/S) and modified Papanicolaou (PAP) stain and to compare the efficacy of modified PAP staining procedure with that of A/S stain and H-E staining technique, so as to device a staining procedure which is easy and effective for keratin. MATERIALS AND METHODS: A Total Number of 60 paraffin embedded tissue sections of known keratin containing tissues including normal keratinized oral mucosa (NKOM), Keratinized Odontogenic Keratocyst (OKC), Verrucous Carcinoma (VC) and Well differentiated Squamous Cell Carcinoma (WDSCC) were taken and 3 sections of 4 microns thickness of each block were cut and stained with above mentioned three stains. RESULTS: Surface keratin was stained distinctly and uniformly in all the three staining techniques in NKOM, OKC, and VC and WDSCC. But results were statistically significant in WDSCC when Amount of keratin pearls and Pattern of staining were compared in all 3 staining procedures and p value was p=0.000 and p=0.001 respectively. CONCLUSION: Based on the above findings we conclude that the efficacy of modified PAP is comparable with that of H-E stain and A-S stain for surface keratin and thus be used effectively to stain Surface keratin. Whereas to know the exact pattern of cytokeratin expression in SCC a more sensitive tool like immunohistochemical method can be applied.