Immunohistochemical Stain-Phosphohistone H3: Most Specific Mitotic Marker.

Introduction: Quantification of Mitotic Figures (MFs) is a prognostic indicator in assessment of Oral Epithelial Dysplasia (OED), Oral Squamous Cell Carcinoma (OSCC) and is part of many histopathological grading systems. Evaluation of MFs is done as part of post treatment (chemoradiotherapy) to monitor any changes in the treated area. But identification and quantification of MFs in routine stains is a tedious process and subjective to errors. Aim: To stain, compare and analyse mitosis specific marker anti-phosphohistone H3 (anti-PHH3) with H&E stain and 1% crystal violet in OED and OSCC. Materials and Methods: Study sample included archival tissues embedded in paraffin blocks histopathologically diagnosed as OED (n=30) and OSCC (n=30). Three serial sections of each tissue specimen were stained separately with H&E stain, 1% crystal violet stain and anti-PHH3 (IHC stain). The stained sections were examined for identification and counting of MFs. The data were analysed using Chi-square test and Kruskal Wallis Test. Results: MFs were significantly increased in OSCC in comparison with OED. There was a significant increase in number of MFs in anti-PHH3 in comparison with crystal violet and H&E stained tissue sections. Conclusion: It was seen that anti-PHH3 is the most specific stain for identification of MFs amongst H&E, crystal violet and anti-PHH3. [ABSTRACT FROM AUTHOR]