Immunohistochemical Expression of Ck8 and Ck18 in Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma - A Retrospective Study On 70 Samples

Abstract

Background: Oral squamous cell carcinoma (OSCC) prevalence is high in India and contributes to about 90% of all oral neoplasms. The 5 year survival rate has not improved even with advances in treatment options. It could be due to delay in patient reporting and lack of proper histopathological examination. Immunohistochemistry helps to confirm the diagnosis in suspicious cases promptly.
Aim and Objectives: Aim of the present study is to identify variations in the immunohistochemical expression of CK 8/18 in normal mucosae, oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC).
Materials and Methods: A total of 70 samples (Formalin Fixed Paraffin embedded blocks) including 10 normal oral mucosa, 30 OPMD and 30 OSCC histologically diagnosed cases were included in the study. Immunohistochemical staining of CK8 and CK18 was performed. The color grading and assessment of IHC staining of the slides was done by two oral pathologists . The data were tabulated and analyzed with SPSS v 22.0 (SPSS Inc, Chicago, IL) using Mean ± SD, ANOVA, Chi Square test Tukey HSD Post-hoc Test. A probability of p<0.05 was considered as significant. Results: The mean score in the control group was 0.9 with standard deviation 1.1. The mean score in the OPMD group was 1.13 with standard deviation 0.8. The mean score observed in the OSCC group was 1.45 with standard deviation 0.86. We performed the Tukey HSD post-hoc test and evaluated that Difference between control and OPMD group was 0.2300, and p value is 0.7606, which did not achieve statistical significance. Difference between Control and OSCC was 0.5500. p value 0.2169, which was not significant. Differences between OPMD and OSCC group was 0.3200 with p value was 0.3520 which also not significant. Conclusion: Strong expression was noted in OPMD and OSCC in our study. There was a progressive increase in its expression from the normal mucosa to OPMD to OSCC but our values did not reach statistical significance. Further investigations will be necessary to explore the mechanisms of CK8/18 expression as well as their exact functions in such cancerous lesions to improve our understanding on tumor biology and its behavior.