Analysis of Histological Prognostic Factors in Colorectal Carcinoma and Relationship of VEGF and E-Cadherin Expression in Prognostic Assessment

Abstract

Colorectal carcinomas (CRC) are associated with several histopathological and molecular factors of prognostic and hence therapeutic implications, including for epithelial mesenchymal transition (EMT) and angiogenesis. Downregulation of E-cadherin is a crucial step in EMT, directly related to tumor progression, invasion, and metastasis. Vascular endothelial growth factor (VEGF) induces angiogenesis and thereby tumour progression and metastases. Our objective was to analyse VEGF and E-cadherin expression in patients with CRC and to effectively assess the relationship of these with histopathological factors. 50 cases of CRC obtained over eighteen months duration, were included in the study. Haematoxylin and Eosin-stained sections were studied for histopathological factors. Immunohistochemistry with E-Cadherin and VEGF were performed on representative sections and evaluated. Histopathological features of importance noted were low grade tumour budding (55.5%), Infiltrative invasive front (83%), lympho-vascular invasion (50%). Preserved expression of E-Cadherin was seen in 66% of the cases, and 34% reduced expression, predominantly noted in patients above the age of 50, increased tumour size, mucinous variants, advanced TNM stage, lymph node involvement and high-grade tumour budding. VEGF staining was seen in 64% of the cases with varying intensity. Increased VEGF expression was noted in poorly differentiated tumours, advanced Duke’s stage and with lymph node metastasis. Colorectal carcinomas with high grade tumour budding were associated with lymph vascular invasion, infiltrative invasive front and significantly correlated with TNM stage. High grade tumours and adverse histopathological prognostic factors revealed a reduced E-cadherin expression and increased VEGF expression.