Immunohistochemical study of HER2/neu expression in colorectal cancer and its relation to other clinicopathological criteria and prognostic factors

Abstract

Background: Human epidermal growth factor receptor 2 (HER2) overexpression and amplification have been studied as a therapeutic and prognostic target in a number of tumors although conflicting data exist about the incidence and clinical consequence of HER2/neu status in the patients with colorectal cancer. The aim of the present study was to evaluate the immunohistochemical expression of HER2/neu and its relationship with clinicopathological parameters and prognostic factors. Methods: This study involved 50 specimens of malignant colorectal cancer lesions and HER-2/neu expression was evaluated by the Hercep-Test Kit. Results: Out of 50 cases, most of them (76%) were HER2/neu negative and in 12 (24%) cases, HER2/neu positive immunostaining were detected. 24% (n = 12), 36% (n = 18), 30% (n = 15), and 10% (n = 5) were scored as 3+, 2+, 1+, and 0 respectively. No significant association was noted between HER-2/neu expression and patients’ age, tumor size, gender, location, grade and stage (P > 0.05). Conclusions: The immunohistochemical evaluation of HER2/neu overexpression for potential targeted anti-HER2 therapy may not be valuable for the patients with colorectal cancer and also studies with larger sample sizes using standardized tests are needed to understand the exact biologic role of HER-2/neu in this type of tumor.