Evaluation of variable p16 immunostaining patterns, Ki-67 indices and HPV status in cervical SILs and squamous cell carcinomas: An institutional experience

Objective: The present study evaluates the immunoexpression of p16 and Ki-67 in cervical squamous intraepithelial lesion (SIL) and carcinomas and correlates their expression with clinicopathological features and HPV-DNA status. Material and Methods: A total 36 included cases of SIL and squamous cell carcinoma (SCC) were subjected to p16 and Ki-67 immunostaining. p16 staining was evaluated depending on grading, distribution, localization pattern, intensity and IHC score. Ki-67 expression was graded based on percentage of positive cells. Results: Incidence of HSIL and SCC cases was found to be significantly increased with parity > 5. p16 grade III diffuse nucleocytoplasmic immunostaining was observed in 62.5% LSIL, 80% HSIL and 87% SCC cases. Significant association of p16 staining intensity, IHC score and Ki-67 indices was noted with increasing grades of SILs and carcinomas. Conclusion: Our experience indicates that a combination of p16 and Ki-67 immunostaining may be useful to determine the severity of dysplastic change.