Expression of EGFR and Ki67 in Oral Squamous Cell Carcinoma and Their Association with Tumor Infiltrating Lymphocytes and Histopathological Parameters

Abstract Background: Oral squamous cell carcinoma (OSCC) accounts for over 90% of oral malignancies and is often associated with poor outcomes when diagnosed at advanced stages. Tumor-infiltrating lymphocytes (TILs), epidermal growth factor receptor (EGFR), and Ki-67 proliferation index are increasingly recognized as important prognostic biomarkers. This study aimed to evaluate EGFR and Ki-67 expression in OSCC and analyze their correlation with TIL density and histopathological parameters. Materials and Methods: An observational study was conducted on 50 histologically confirmed OSCC cases over 1 year. Clinical details, tumor site, grade, stage, and TIL levels were documented. Immunohistochemistry for EGFR and Ki-67 was performed using rabbit monoclonal antibodies. Associations between TILs, EGFR, Ki-67, and clinicopathological variables were analyzed statistically. Results: The mean age of patients was 46.1 ± 9.8 years, with buccal mucosa being the most frequent site (66%). Most of the tumors were well-differentiated (82%). Pathological staging revealed pT3 in 36% and pN0 in 68% of cases. High EGFR expression was noted in 78% of tumors, while 70% showed Ki-67 >10%. Stromal TILs were high in 48% and moderate in 46%, whereas intra-tumoral TILs were predominantly low (76%). A statistically significant association was found between stromal TIL levels, Ki-67 expression, and EGFR positivity ( P < 0.05). Conclusion: Stromal TIL density correlates significantly with EGFR and Ki-67 expression in OSCC, suggesting that combined assessment of these biomarkers may provide valuable prognostic insight. Their integration into routine histopathological evaluation could improve risk stratification and guide personalized therapeutic approaches.