Immunohistochemical expression and prognostic value of epidermal growth factor receptor 1 and human epidermal growth factor receptor 2/neu in primary colorectal carcinoma

Abstract

Objectives Colorectal carcinoma (CRC), a highly heterogeneous disease, is the seventh most common cancer in Egypt. Human epidermal growth factor receptor 1 (EGFR1) and human epidermal growth factor receptor 2 (HER2/neu) are biomarkers that have been introduced recently for patient stratification, prediction of prognosis, and implementation of personalized therapy. Therefore, this study aimed to investigate the immunohistochemical expression of EGFR1 and HER2/neu in primary CRC patients and their relations with clinicopathological parameters and overall survival (OS). Patients and methods Sixty-six patients with primary CRC from the National Cancer Institute of Egypt were enrolled in this study. Paraffin blocks were collected and sectioned for histopathological evaluation. Other sections were stained using anti-EGFR1 and anti-HER2/neu monoclonal antibodies. Results Cytoplasmic and membranous EGFR1 was expressed in 81.8% of cases, while complete membranous HER2/neu-positive staining (>10% of tumor cells) was detected in 2/3 of cases. The EGFR1 expression was significantly associated with advanced stage and positive lymph node status. None of the other parameters, including overall survival, showed a significant relation with the expression of both markers. Conclusion In conclusion, EGFR1 and HER2/neu proteins were highly expressed in the CRC cases investigated. EGFR1 expression was significantly associated with indicators of poor prognosis (advanced tumor stage and nodal positivity). Both markers showed a tendency toward worse survival.