A Study of Podoplanin Immunohistopathological Expression in Oral Squamous Cell Carcinoma and Its Associated Stroma

Abstract

Background: Oral squamous cell carcinoma (OSCC), the most common carcinoma in the head and neck region, accounts for ninety percent of the malignancies in the oral cavity and ranks among the top eight causes of cancer-related death globally. The expression of podoplanin, transmembrane mucin-like glycoprotein, is up-regulated in a number of different human cancers, including squamous cell carcinoma of the oral cavity, and its relationship with tumour invasion raises the possibility that podoplanin expression could be used as a biomarker for diagnosis and prognosis. Aim of the Study: the aim of this present study is to evaluate the expression of podoplanin in the three different grades of the oral squamous cell carcinoma and its associated stroma for understanding of the microenvironment of the tumour for better and early diagnosis. Materials and Methods: In this retrospective study, 45 formalin fixed, paraffin embedded blocks of excised tumours from patients with oral squamous cell carcinoma, included 15 cases for each grade of OSCC, treated with Haematoxylin and Eosin for routine staining, and podoplanin D2-40, monoclonal antibody, for immunohistochemical staining. Results: In this present study, we found insignificant association between the clinicopathological characteristics and the three grades of OSCC. A highly immunoexpression of podoplanin revealed through the three grades of OSCC (88.8%) of cases with the high immunoreactive score mostly found in poorly differentiated OSCC and the low immunoreactive score mostly found in well differentiated OSCC (P = 0.017). The assessment of lymphovascular density in peritumoral and intratumoral lymph vessels revealed up-regulation from well to poorly differentiated OSCC with highly significant association in the peritumoral lymph vessels (p = 0.007), and in the intratumoral lymph vessels (p = 0.020). A highly significant association found during the assessment of the distribution of inflammatory cells in the three different grades of OSCC from well, moderately to poorly differentiated OSCC (p = 0.000). Conclusions: Podoplanin seems to be helpful as a biomarker for early detection of oral squamous cell carcinoma, and it may play an important role for the detection of the advanced grades of oral squamous cell carcinoma. Moreover, podoplanin can be used in lymphangiogenesis assessment of oral squamous cell carcinoma.