Role of Perfusion C.T. in Colorectal Cancer

Abstract

An Egyptian study at national cancer institute, Cairo university showed that, rectal carcinoma constituted approximately only 2.2% of newly diagnosed cancer patient in 2005, that is representing 12.4% of the tumors of the digestive tract (Annual Cancer Conference of the Egyptian Cancer Society, Danish Cancer Society & Aarhus University Hospital February, 2005). American cancer society, considered that the survival of the patients with colorectal cancer depends to a large extent on the stage of the disease at diagnosis. Microvessels density has been established as a prognostic indicator for many cancers, and the most direct strategy to monitor anti-angiogenic therapy would be periodic biopsy which is invasive approach, hence the need for non-invasive method to assess the tumour vascularity and give accurate results for post therapeutic assessment. CT perfusion is useful and non invasive technique for evaluating colorectal malignancies. Malignant and normal tissue can be accurately differentiated using perfusion maps. Perfusion CT is found to be helpful in oncology with a wide array of application in tumour diagnosis, staging, prognostic evaluation and monitoring therapeutic response. Perfusion CT involves dynamic scanning after the administration of iodinated contrast material followed by mathematic modeling to study contrast material kinetics in the tissue. Estimation of tumour perfusion parameters such as blood flow , blood