IMMUNOHISTOCHEMICAL EXPRESSION OF STEM CELL MARKERS CD44, CD166 AND ALDH1A1 IN NON-NEOPLASTIC POLYPS OF THE COLON IN SAMPLE OF IRAQI PATIENTS

IMMUNOHISTOCHEMICAL EXPRESSION OF STEM CELL MARKERS CD44, CD166 AND ALDH1A1 IN NON-NEOPLASTIC POLYPS OF THE COLON IN SAMPLE OF IRAQI PATIENTS Nawal M Abdullah*, Mustafa M Ibraheem@ & Basim Sh Ahmed# *MB,ChB, MSc, Assist. Prof., Department of Anatomy, College of Medicine, University of Basrah. @MB,ChB, MSc, PhD, Assist. Prof., Department of Anatomy, College of Medicine, University of Al-Mustansiryah. #MB,ChB, FICMS, Assist. Prof. Department of Pathology, College of Medicine, University of Al-Mustansiryah, IRAQ. Abstract The aim of this retrospective study on tissue specimens of benign colorectal polyps is to evaluate the significance of IHC markers CD44, CD 166 and ALDH1A1 expression in non-neoplastic (Juvenile and Hamartomatous) polyps and their association with different clinicopathological parameters & to compare their expression in benign polyps with that of normal colonic tissue . Seventy cases enrolled in the study including benign polyps (juvenile & hamartomous polyps) & benign looking colonic tissue obtained from archive of histopathology unit in Gastroenterology and Hepatology hospital in Baghdad Medical City and histopathology unit in Al-Sadder Teaching Hospital in Basrah city for the period Sept. 2015 to Dec. 2016. Four micrometer sections were obtained from formalin fixed paraffin-embedded blocks treated IHC with CD44, CD166 and ALDH1A1 tumor markers. Majority of polyps were juvenile, no difference regarding gender distribution. The common location was rectum/rectosigmoidal region. CD166, CD44 and ALDH1A1 showed high expression regarding age, gender and location in benign tumors when compared with healthy looking tissue. In conclusion, colorectal polyps are critical clinical entity and many of them are a precursors to malignant diseases so colonoscopy is essential screening test, polypectomy and follow up is mandatory for patients with colorectal polyps even if they are benign.