Overexpression of Her2/Neu in Gastric Carcinoma: association with histological type, tumor grade and H. Pylori infection

Introduction: Gastric cancer is the second leading cause of cancer mortality in the world and its management, especially in advanced stages, has evolved relatively little. In particular, no targeted modality has so far been incorporated for treatment. HER2 over-expression is increasingly recognized as a frequent molecular abnormality, driven as in breast cancer by gene amplification. There is mounting evidence of the role of HER2 over-expression in patients with gastric cancer, and it has been strongly correlated to poorer outcomes and a more aggressive disease. Aims and objective: The purpose of this study is to establish the clinicoepidemiological, histopathological and immunohistochemical particularities of the gastric carcinomas, and to identify the factors with a prognostic value. Methods:  The present study included 54 cases of gastric carcinoma, who had undergone endoscopy guided biopsy or gastrectomy. Expression of HER2 oncoprotein by immunohistochemistry and detection of  Helicobacter pylori was done using modified Giemsa stain. Expression of HER2 was correlated with patient’s clinicopathological parameters. Results:  HER2+ rates were 22.22% (12/54). HER2 over-expression was associated with poorly differentiated carcinoma ( P = 0 . 0159) and intestinal type of gastric carcinoma (P=0.0245). Conclusion:  In this study, HER2 expression was seen more in intestinal type of gastric carcinoma as compared to the diffuse type involving mostly poorly differentiated cases. Regarding H. pylori, we found no correlation between its presence and the over-expression of HER2. So, the results of this study may contribute to a better knowledge of the efficacy of trastuzumab-based therapy in HER2 positive gastric cancers but the outcome of anti H. pylori medication in HER2 positive cases still remain inconclusive.