Assessment of Immunohistochemical Expression of CD44 in Colorectal Adenoma and Colorectal Carcinoma

Background: Colorectal cancer (CRC) is a foremost global health concern and remains one of the major causes of cancer-related morbidity and mortality. It is the third most common cancer in adults after lung cancer and breast cancer worldwide. The theory that cancer originates from a subpopulation of tumor cells, named cancer stem cells (CSC), they have an important role of CSC in the initiation and maintenance of the tumor, as well as invasion, metastasis, and therapeutic resistance. Among CSC markers, CD44 is the most investigated colorectal CSC markers. This study aims to assess the immunohistochemical expression of CD44 in colorectal adenomas & CRCs. And its relation between immunohistochemical expression of CD44 with tumor differentiation (grading), lympho-vascular invasion, perineural invasion, desmoplasia and TNM stage. Methods: this is a retrospective descriptive study that included Sixty paraffin embedded blocks from the pathology laboratory, Suez Canal University Hospital. Paraffin blocks included (14 cases of colorectal carcinoma and 18 cases of colorectal adenoma). paraffin blocks reviewed for clinicopathological prognostic factors and stained by CD44, monoclonal antibodies by immunohistochemical method. Results: The CD44 protein was overexpressed in 80% of CRC, while was positive (44.4%) in adenoma this difference was statistically. Conclusions: CD 44 is highly expressed in large number of CRC (80 of tumors). It is also significantly more expressed in CRC than in adenomas, suggesting a role of CD 44 in CRC tumorigenesis and progression of adenomas into carcinomas. Our study also associated CD 44 overexpression with both late TNM stage and lympho-vascular invasion.