Assessment of HER2/Neu Expression in Colorectal Carcinomas and Its Correlation With Tumor Stage and Histopathology

Introduction Colorectal carcinoma (CRC) is the second leading cause of cancer-related mortality worldwide. Within this context, a subset of CRCs shows overexpression of the human epidermal growth factor receptor 2 (HER2/neu), a characteristic also seen in other malignancies like breast and gastric cancers. The success of targeting the HER2 pathway in these cancers has prompted investigations into the potential use of similar interventions in CRC. Aims This research aims to assess HER2/neu expression in CRCs and its correlation with the CRC stage and histopathology, as well as to evaluate the demographic characteristics of CRC patients. Materials and methods This prospective observational study was conducted on a cohort of 40 CRC patients, using histopathology and immunohistochemistry (IHC) sections from the Department of Pathology. Clinical and demographic data were collected over a 24-month period, and routine tissue processing and IHC staining were performed on colectomy tissues. Immunostaining with the HER2/neu marker was conducted for detailed analysis. Data were analyzed using IBM SPSS Statistics for Windows, Version 27.0 (Released 2020; IBM Corp., Armonk, NY, United States). Results Among the 40 CRC cases studied, six cases (15%) exhibited robust membranous positivity, while eight cases (20%) showed moderate focal membranous positivity. Twenty-six cases (65%), however, demonstrated no HER2/neu staining positivity. A significant correlation was found between the histological grade of the tumor and HER2/neu expression (p = 0.0001). Additionally, HER2/neu expression was significantly correlated with lymphovascular invasion (p < 0.0001) and lymph node status (p < 0.047). Conclusion This study found a strong correlation between the tumor's stage, grade, lymph node status, and lymphovascular invasion and HER2/neu expression. Therefore, HER2/neu can be a predictive and therapeutic marker in colorectal cancers. This underscores the potential importance of incorporating these parameters in the clinical evaluation and targeted treatment strategies for CRC patients.