Immunohistochemical expression of HER2/neu in colorectal carcinoma in Erbil city, Kurdistan Region


Background and objective: Colorectal carcinoma is one of the commonest cancers and the second leading cause of cancer death in Europe and North America. Despite the improved surgeries and adjuvant therapies, the prognosis of colorectal cancer remains poor, and the survival rate is unsatisfactory. Overexpression of HER2 gene has been noticed in many human cancers, and it is associated with poor prognosis. This study aimed to detect the frequency of the HER2/neu immunoexpression in colorectal carcinoma and investigate its association with the clinicopathological parameters.Methods: A retrospective study was carried out in Rizgary teaching hospital and private laboratories in Erbil city for the period from January 2014 - December 2017. A total of 103 formalin fixed, paraffin embedded, archival tissue blocks of colectomy samples of colorectal carcinoma cases were collected. Immunostaining was done in a private laboratory (Vin Lab) in Dohuk city. Scoring of the HER2/neu immunostaining was managed according to published criteria for breast carcinoma.Results: Fifty-five cases (53.4%) were labeled as positive for HER2/neuimmunoexpression. While 48 (46.6%) of the cases were labeled as negative. HER2/neu status was significantly associated with the tumor grade (P = 0.02), while no significant association was found between HER2/neu expression and other clinicopathological parameters.Conclusion: HER2/neu immunoexpression was observed in 53.4% of the cases of colorectal carcinoma, and it was significantly associated with tumor grade.