ABSTRACT
To improve the diagnosis of concomitance of cancer and cyst in the same kidney, a retrospective review of the imaging results of 10 patients with cystic renal cancers confirmed by surgery and pathologic study was performed. Excretory urography showed an avascular mass suggestive of a cyst. Ultrasonography revealed a cystic mass with thinkened and irregular walls,but it was unable to distinguish between a complicated and an extensively necrotic cancer.On CT scans,irregular cystic wall and definite early enhancement in solid component were observed.In some of the patients,there were mural nodules,septum and calcification. Some scans may show an almost cystic appearance,but one or more CT scans always showed some dense neoplastic tissue.This study indicated irregular and thickened cystic wall and septum,mural nodules and early enhancement of solid component were the characteristic findings for the CT diagnosis.This suggestive CT pattern must be particularly searched for at the base of the cyst,but may also be present in the periphery of the cyst.