P16 and EGFR analyses in cervical carcinoma on paraffin material in Egyptian females: the NCI experience

Abstract

Introduction Cervical cancer is considered the fourth most prevalent malignant tumor in women worldwide. In Egypt, it ranks as the 14th most frequent cancer among women. Epidermal growth factor receptor has been an attractive target for anticancer therapy. Although EGFR mutations are less commonly seen in cervical cancer, there is a potential correlation between EGFR expression level and clinical response. Overexpression of p16INK4a is associated with increased overall and disease-free survival in cervical cancer, thus denoting a better prognosis. Aim of the work To investigate the expression of EGFR and p16 by immunohistochemistry as well as amplification of EGFR by FISH technique in cervical carcinoma among Egyptian females. Material and methods Seventy-seven cases of invasive cervical carcinomas were retrieved from paraffin blocks. EGFR and p16 expression were assessed by immunohistochemistry. EGFR gene amplification was assessed by FISH analysis. Results p 16 Positivity was detected in 62.3% of cases. Positive reaction to EGFR (score 3+) was detected in 20.8% of cases. The EGFR gene was not amplified in 77.9% of cases. Statistical significance was found between histological type, p16, and EGFR expression. A fair agreement was detected between EGFR expression and EGFR amplification. Poor agreement was detected between p16, EGFR expression, and EGFR amplification. Conclusion EGFR and p16 have an independent role in the development of cervical cancer in Egyptian females. EGFR overexpression and EGFR amplification represent two different genetic events; in other words, an increase in gene copy number does not mean that there will be an increase in the function of the gene as expressed by an increase in protein expression.