Immunohistochemical Study of CEA and BCL2 Expression in Colorectal Adenocarcinoma and its Correlation with Some Pathological Parameters


Background :- Colorectal cancer is the second most prevalent cancer and the fourth leading cause of death[1]. In Iraq and according to the Iraqi cancer registry reports in 2002 , the incidence of colorectal carcinoma was 4.55% of whole body malignancy, & it is the seventh cause of death from cancer[3]. Immunohistochemical studies have revealed that CEA is a product of normal as well as cancerous colonic cell and that the difference in CEA content between the cancerous and the normal colorectal mucosa is quantitative and not qualitative[9-11], Expression of bcl-2 has been studied in a number of human tumors, including colorectal carcinoma. Non-small-cell lung carcinomas[18] breast carcinomas[19,20] and neuroblastomas[21] all express bcl-2, and studies have been published correlating expression with survival. Similarly, a number of studies[22-26] have been published evaluating the clinical use of bcl-2 immunohistochemical expression as a prognostic factor. Aim of the study :- The aim of our study was to estimate possible correlations between the CEA and BCL-2 immunohistochemical expression and some pathological parameters in colorectal adenocarcinoma like grade , stages and site of tumor Material and method: - thirty nine patients of colorectal carcinoma studied in Al- Diwanyia teaching hospital during a three years period (July 2008 - December 2010) were studied. There were 30 males and 9 females with a median age of 58 years (range 26-90 years). A manual avidine-biotin-peroxidase complex procedure was used in the immunohistochemical analysis (DakoCytomation, Copenhagen, Denmark). Result :- all the studied cases were positive for CEA (100%) and out of 39 cases there were only 23(58.9%) cases positive for BCL2 expression , also this study showed significant relationship between expression of CEA and grades and site of tumor while BCL2 significantly correlated with grades and stages of the tumor.Conclusion :- From the present study we may conclude that CEA and BCL-2 have a similar pattern of expression in primary colorectal adenocarcinoma although BCL-2 expression in colorectal adenocarcinoma is more restricted than CEA expression