Evaluation of p53 and Ki-67 Expression in Cervical Intraepithelial Neoplasia (CIN) and Invasive Cervical Cancer: A Prospective Observational Study

Abstract

 Introduction: Cervical cancer is the fourth most common malignancy among women worldwide, predominantly affecting those in low- and middle-income countries due to inadequate screening and preventive measures. High-risk Human Papillomavirus (HPV) infection, particularly types 16 and 18, is a critical etiological factor in cervical carcinogenesis. Molecular markers like p53 and Ki-67 have emerged as valuable indicators of disease progression and prognosis, given their roles in cell cycle regulation and proliferation. Aim and Objective: To evaluate the expression of p53 and Ki-67 in cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma, and to correlate their expression with histopathological grades. Materials and Methods: This 15-month prospective observational study at GSVM Medical College, Kanpur, and J.K. Cancer Institute included histologically confirmed cases of CIN (I, II, III) and invasive cervical carcinoma in women aged 18 and above. Immunohistochemistry (IHC) assessed p53 and Ki-67 expression, with chi-square tests and p-values used to analyze associations between biomarker expression and histological grading. Results: The study included 100 participants with a mean age of 41.66 ± 12.00 years. Squamous cell carcinoma (SCC) was the most common (40%), followed by CIN3 (30%), CIN2 (20%), and CIN1 (10%). High Ki-67 expression was mainly seen in SCC and CIN3 (p < 0.0001).Aberrant p53 expression was rare (1.6% in SCC), while mild reduction was common in CIN3 (19.4%). Conclusion: The findings suggest that high Ki-67 expression and reduced p53 levels are associated with greater histological severity in cervical lesions. These markers hold significant prognostic value and could enhance early diagnosis and targeted therapeutic strategies in cervical cancer.