Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 47 3 2009 06 15 161 164 EN Nourieh Sharifi Department of Pathology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Kamran Ghaffarzadegan Department of Pathology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Hossein Ayatollahi Department of Pathology and Hematology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Mohammad Taghi Shakeri Department of Community Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Mohammad Hadi Sadeghian Department of Pathology and Hematology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Jafar Bordbar Azari Department of Pathology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. 2015 09 28 The basic pathogenic step in the process of tumor growth, invasion and metastasis is tumor-induced angiogenesis. The aim of this study was to evaluate the angiogenesis in colorectal carcinoma by microvascular density (MVD) determination with IHC (immunohistochemistry) method and to determine if and how angiogenesis correlates with clinicopathologic parameters. Sixty two archival, paraffin embedded tissue samples of colorectal carcinoma from Omid Hospital (Mashhad, Islamic republic of Iran) were selected. Microvessels were identified immunohistochemically, using monoclonal CD34 antibody. Two investigators examined the microvessel density then the median value of MVD was determined and correlated with clinicopathologic parameters. Tumor-induced angiogenesis of colorectal carcinoma statistically correlated with histological tumor grade (P=0.000). There was no significant correlation between intratumoral microvessel density and sex and age of patients, localization, and stage and histologicalal tumor type (P > 0.1). Intratumoral microvessel density quantification in histologic specimens of colorectal carcinoma reflects the grade of tumors and may be a useful additional prognostic factor. https://acta.tums.ac.ir/index.php/acta/article/view/3567 https://acta.tums.ac.ir/index.php/acta/article/download/3567/3543