ABSTRACT
The immunological assessment at molecular profiling of K-Ras, p53 and Ki-67 along with EGFR, BRAF and others like BCL-2 has been the focus of several workers. The incidence of colorectal adenomatous polyp with dysplastic changes and colorectal carcinoma per se in the context of Indian population as per the ICMR registry, New Delhi, India, is significant. We wanted to study precancerous lesions (adenoma, polyp) and adenocarcinoma of colorectum for the expression of K-Ras, p53 and Ki-67 in biopsy or surgical specimen of colon by immunohistochemistry for its occurrence. We also wanted to study the intratumor heterogeneity of aforesaid expression for the purposes of prognostication and correlation with other clinicopathological parameters. MethodsThis is a cross sectional study conducted in the Surgical Pathology and Division of Immunohistochemistry, Department of Pathology, Jawaharlal Nehru Medical College, Sawangi (Meghe), Wardha, Maharashtra, India, for a duration of 2 years. Total seventy patients of all ages and genders suspected of 1) precancerous lesions of adenomas and polyps (35 cases) and 2) adenocarcinoma on colonoscopic biopsy or surgical specimens (35 cases) were included in the study. The expression of K-Ras, p53 and Ki-67 as primary objectives along with EGFR, BRAF and others like BCL-2 as secondary objectives were recorded, tabulated and compared for the purposes of predictive parameters in colorectal neoplastic lesions. ResultsMost of the cases of CRC were over the age of 50 years and Male:Female ratio was 5:3.Twenty-five cases of group 2 (CRC) showed positive IHC for K-Ras. p53 was detected in 28 cases and high Ki-67 index was observed in all 32 cases of CRC. The comparative statistics in the pilot study showed that the immunoexpression of K-Ras, p53 and Ki-67 is significantly higher in group 2 (CRC) compared to cases in group 1 (polyps) and group 3 (normal). ConclusionsExpression of K-Ras, p53 and Ki-67 is likely to be the distinguishing tissue biomarkers between benign and malignant colorectal disease process as well as have prognostic and predictive value in colorectal cancer. The addition of EGFR, BRAF and BCL-2 would help in determining the pathogenesis and offer targeted therapeutic intervention.