A Study of D2-40 Immunohistochemical Expression in Colorectal Carcinomas

Abstract

Background: Colorectal cancer is one of the most common cancers. Factors affecting survival include nodal positivity, lymphovascular invasion (LVI) and lymphangiogenesis (role in metastasis). Most endothelial markers stain lymphatics and blood vessels without discrimination. Recent marker D2-40 is specific for lymphatic endothelium.This study aims to interpret the utility of D2-40 in detecting LVI, which would be missed on H&E; and in analysing lymphatic vessel density and LVI as predictive markers for the risk of nodal metastases in colorectal carcinomas.Methods: Study was conducted on 40 specimens of colorectal carcinomas. Immunohistochemistry was performed with D2-40. Stastical analysis was by Spearman's correlation and Chi square test Result: Mean age was 55.50 years. Of 40 cases, majority were in ascending colon followed by rectum, sigmoid, transverse and descending colon. 80.0% were adenocarcinomas, 15.0% mucinous adenocarcinomas and 5.0% signet-ring cell carcinomas. Tumors were moderately differentiated in 80.0% and poorly in 20.0%. Most patients were in stage T3 followed by T2 and T4. Most common nodal stage was N0 followed by N1, N2 and N3.LVI was detected in eleven more cases on D2-40 than H&E and correlated with lymphatic density and nodal status. Lymphatic density correlated with nodal status and pT. Peritumoral lymphatics were found in 95% cases and intratumoral lymphatics in 90%. Intratumoral lymphatics correlated with nodal status.Conclusion: D2-40 increased the detection rate of LVI as compared to H&E and showed the value of lymphangiogenesis in disease progression and metastasis.