Study of human epidermal growth factor receptor (HER2/neu) expression in primary colorectal carcinoma in a tertiary care hospital

Abstract

Introduction: Colorectal cancer (CRC) mainly affects the middle-aged and elderly population with a gradual increase in its incidence. Various studies have found human epidermal growth factor receptor (HER2/neu) overexpression in CRC and its associated prognostic outcome. HER2/neu activates various signaling pathways which leads to cell proliferation and survival, and thereby its overexpression causes excessive tumor cell growth and migration. Aims and Objectives: The aim of this study was to determine the percentage of HER2/neu positive and negative cases and to correlate it with the grade and stage of the tumor. Materials and Methods: The study was carried out for 2 years in the Department of Pathology, MGM Medical College and Hospital, Aurangabad, and included 35 resected specimens of colorectal carcinoma. Histopathological examination was studied and for immunohistochemical (IHC) staining, paraffin wax-embedded tissues were immune stained for HER2/neu. Results: Of 35 cases, there were 18 women and 17 men. Approximately 28.57% cases were in the age group of 41–50 years with the mean age being 54 years. In 37.14% of cases, the tumor was located in the ascending colon. Approximately 77.14% cases were Grade 2. In total, 57.14% cases were at stage T3. Six cases were HER2/neu positive and 29 cases were HER2/neu negative. Conclusion: A significant correlation was found between HER2/neu expression with histologic grade and stage of the tumor. HER2/neu targeted therapeutic strategies have the potential to change treatment course and outcome. Hence, HER2/neu can be used as a biomarker in patients with CRC to assess their prognostic outcome.

Keywords

• colorectal cancer
• her2/neu
• immunohistochemistry