Normal excretory urography in patients with primary kidney neoplasms

The records of 65 consecutive patients discharged from the hospital with a diagnosis of primary parenchymal neoplasm of the kidney were reviewed. Four of the 65 patients had neoplasms which were not detected by excretory urography. The 4 undetected lesions included 3 renal cell carcinomas and 1 oncocytoma. All of these lesions projected from the anterior or posterior surface of the kidney, and all 4 were clearly demonstrated by computed tomography. Normal findings on an excretory urogram do not completely exclude a neoplasm of the kidney. When there is strong clinical suspicion of a renal neoplasm, computed tomography should be the initial examination or should be done even if the urogram has shown normal findings.