To Correlate the Expression of KRAS and BRAF V600e with Histological Grades and Variants in Tissue Samples of Colorectal Carcinoma

Abstract

OBJECTIVES This study aimed to correlate the expression of KRAS and BRAF V600E with histological grades and variants in tissue samples of colorectal carcinoma. METHODOLOGY In this cross-sectional study total of 51 cases of Colorectal cancer (CRC) were analyzed for immunohistochemical staining using KRAS and BRAF antibodies on representative tissue blocks. Clinical and pathological records were retrieved for the collection of data. The results of the immunohistochemical analysis were correlated with the recorded clinicopathological parameters. RESULTS Fifty-one cases of CRC were analyzed for immunoexpression of KRAS and BRAF V600E. The age of the patients ranged from 14 to 85 years, with a mean age of 60.96 years. Among the 51 cases, 37(72.5%) cases were males and 14(27.4%) were females. 37(72.5%) were localized to left side colon and 14(27.4%) were found in the right colon. For KRAS immunostaining, 41(80.3%) out of 51 cases showed overexpression, while the remaining 10(19.6%) cases revealed negative expression. In the case of BRAF V600E, positive expression was seen in 20(39.2%) cases, whereas 31(60.7%) cases showed negative expression of BRAFV600E. A significant association was seen between KRAS overexpression and histological variants, i.e. glandular carcinomas. CONCLUSION Over-expression of KRAS was observed in advanced tumors. The presence of BRAF V600E mutation in the present study signifies the importance of BRAF V600E inhibitors as a potential alternate therapeutic tool in EGFR inhibitors and chemotherapy-resistant tumors.

Keywords

• Colorectal cancer
• KRAS & BRAF V600E Immunohistochemistry
• Tumor Grades, Histological Variant