Localization of small renal tumor by dynamic computerized tomography

Herein we report on 4 cases of renal tumor whose diameter was less than 3 cm. A mass lesion was suggested by renal echography in mass screening program. Renal dynamic computerized tomography (CT) with bolus injection can delineate a mass lesion clearer than ordinary plain and enhanced CT, and renal angiography. In renal dynamic CT, tumor lesion is well depicted because of the difference between the time density curve in the tumor lesion and that in the surrounding renal parenchyma. Renal dynamic CT is considered to be an especially versatile modality to diagnose small tumors which are hardly delineated by ordinary enhanced CT.