Expression of Osteopontin in Oral Squamous Cell Carcinoma and its Surgical Margins-An Immunohistochemical Study

Abstract

Introduction: Despite the advances in the treatment modalities offered for oral squamous cell carcinoma. The recurrence rate of it still remains quite high. Early detection of recurrence will improve the outcome and the survival of the patient. Osteopontin, a transformation–related phosphorylated protein in epithelial cells has been closely related with tumourigenesis. This study was undertaken to explore the potential of OPN as a tumour marker of recurrence in OSCC. Aim: To analyse the expression of Osteopontin (OPN) in Oral Squamous Cell Carcinoma (OSCC), patient matched tumour free surgical margins and normal oral mucosa and to correlate with local & loco regional recurrence. Materials and Methods: Twenty cases each of formalin fixed paraffin embedded blocks of histopathologically diagnosed cases of OSCC, patient matched tumour free surgical margins and normal oral mucosal tissues were obtained from the archives of the Oral Pathology & Microbiology Department, Faculty of Dental Sciences, SRU and Govt. Arignar Anna Memorial Cancer Hospital, Kancheepuram. Immunohistochemical analysis was performed with an antibody to Osteopontin protein. Patients with secondary tumours and those treated with chemotherapy and radiotherapy were excluded from this study. Results: The expression of OPN was elevated in 95% of tumours & 55% of histologically tumour free margin samples. There was negative OPN expression in normal mucosal samples. The result of the study was statistically analysed using Pearson chi-square test and was found to be statistically significant. Conclusion: OPN can be used as a diagnostic marker in Oral Squamous Cell Carcinoma. In the tumour free surgical margins, elevated levels of OPN may predict a significantly increased risk of recurrence.

Keywords

• immunohistochemistry
• surgical margins
• recurrence
• tumourogenesis