Original Research Article DOI: 10.18231/2394-6792.2017.0096 Indian Journal of Pathology and Oncology, July-September 2017;4(3):446-449 446 HER 2/neu as a theranostic marker in colorectal carcinoma and its relationship with histopathological correlates-A pilot study G. Priyanka 1 , Leena Dennis Joseph 2,* , G. Barathi 3 , Monica Kumbhat 4 1 UG Student, 2 Professor, 3 Assistant Professor, 4 PG Student, Dept. of Pathology, Sri Ramachandra University, Chennai *Corresponding Author: Email: leenadj@gmail.com Abstract Introduction: Colorectal carcinoma(CRC) is one among the many leading causes of cancer related mortality worldwide. The survival rate of patients with CRC is better because of advancements made in the treatment modalities, in terms of surgery and chemotherapeutic options. This study is done to know the immunoexpression of Her 2/neu in CRC and its correlation with histologic grades. Her 2/ neu is considered to be a beneficial Immunohistochemical (IHC) marker for colon cancer which can be used for predicting the prognosis and for targeted therapeutic modality. Materials and Method: The present pilot study was done to understand the expression of Her 2 /neu in histologically proven 25 cases of adenocarcinoma colon using monoclonal anti Her 2 /neu antibody (Biogenix). Positivity was recorded as per the consensus panel recommendations on Her 2/neu scoring. (1) The clinical profile of the patients were obtained from the archives in the Pathology department of our institution. Results: This study had a total of 25 hemicolectomy specimens of colorectal carcinoma. Of the total 25 cases, 14 cases (56%) were males and 11 cases (44%) were females. Forty percentage of patients were in the age group of 50-60 years. Histopathologically, most of them were adenocarcinomas. Her 2/neu expression was negative in all the 25 cases of colorectal carcinoma in our study. The control tissue was Her 2 /neu positive breast carcinoma with complete membrane staining in the tumor cells(3+). Conclusions: Her 2/neu is considered as a therapeutic modality in advanced and metastatic CRC cases. This was a pilot study and we need to perform the IHC stain on more cases to understand its expression in our population. Keywords: Colorectal carcinoma, Her 2/neu, Immunohistochemistry Manuscript Received: 9 th May, 2017 Manuscript Accept: 1 st June, 2017 Introduction Colorectal carcinoma(CRC) is one of the most prevalent cancers in men and women and is among the leading cause of morbidity and mortality. Even with excellent surgical and chemotherapeutic regimens, CRC remains as one of the leading causes of cancer related mortalities worldwide (2) Further advances have been made with identification of biological markers for targeted therapy. Treatment with Anti Epidermal growth factor(EGFR)monoclonal antibody with the use of drugs like cetuximab and panitumumab, has been documented to show a progression free survival in advanced CRC cases with wild type KRAS. Even with these advances, many patients respond poorly to treatment and at times their response is totally unpredictable. Thus extensive research is on, to discover new molecular biomarkers which can improve outcome, therapeutic response and potential targets in CRC patients. The Vascular Endothelial growth factor(VEGF) A is an angiogenic factor that is produced by the tumor cells, the function of which is neoangiogenesis. This mechanism promotes metastasis by promoting the leakage of blood vessels for vascular invasion (3) VEGF expression has been shown to be upregulated in many tumors and is of prognostic value. Treatment with bevacizumab, antibody against VEGF, shows significant improvement in patient outcome. Recently Her 2/neu was found to be closely associated with VEGF expression. The Her 2 /neu oncogene, also called c-erbB2 codes for a transmembrane tyrosine kinase receptor which is, homologous to EGFR. This receptor is involved in the growth and progression of the malignant cells. Over expression of this protein is demonstrated in 25 to 35% of breast cancers. (4) Treatment of these patients with trastuzumab (herceptin), an anti Her 2/neu monoclonal antibody has been shown to reduce the bulk of tumor, improve response to chemotherapy, thus improving survival in primary and metastatic breast cancers. (5) The role of herceptin is evaluated in CRC also for therapeutic benefits for the patients. Material and Method Institutional Ethics clearance was obtained for the study. The cases were selected from the pathology case files. Twenty five hemicolectomy specimens were taken in the study group. Clinical profile of these patients were recorded from the case sheets. All the Hematoxylin and Eosin stained slides of these cases were reviewed and appropriate slide was selected, which had both normal colonic tissue and tumor. The block corresponding to the selected slide was used for cutting sections for the immunohistochemistry(IHC).