Immunohistochemical expression of EGP40, a tumor marker, in different grades of oral squamous cell carcinoma

AIM: The aim of this study was to see the distribution and pattern of staining of epithelial glycoprotein 40 EGP-40 (also known as GA733-2, ESA, KSA, 17-1A antigen) in the different grades of OSCC. MATERIALS AND METHODS: 30 biopsy reports retrieved from the files of the Department of Oral Pathology and Microbiology, College of Dental Surgery, Manipal were used. These comprised of 10 microslides each of 3 different histological grades of Oral Squamous Cell Carcinoma, namely Well Differentiated, Moderately Differentiated and Poorly Differentiated carcinomas. Immunoperoxidase staining for IgG, was performed by the unlabelled antibody peroxidase-antiperoxidase complex (PAP) method. The criteria used to define an antigen positive area were: Homogenous /Patchy staining of the section and Cytoplasmic/ Membranous staining of the tumor cells. RESULTS: The expression of EGP 40 in different grades of OSCC showed an inverse relationship to differentiation and a direct relationship with the proliferation of the tumor cells and its expression became more pronounced as the grade worsened i.e. from well to poorly differentiated OSCC. CONCLUSION: In the present study, the surface antigen EGP40 (Ep-CAM) was detected in the different grades of OSCC with its expression becoming more pronounced as the grade worsened i.e. from well to poorly differentiated OSCC. However, further studies are required to understand the dualistic role of EGP40 (Ep-CAM) in mediating cell to cell adhesion preventing cell scattering and its heterogeneous expression in promoting tumor invasion and metastasis and also to determine its exact role and significance at a practically applicable level.