[Computed tomography for the diagnosis of a renal mass].

The accuracy of differential diagnosis of renal mass lesions by computed tomography (CT) was evaluated. A retrospective study was done on 23 patients with renal mass lesion suspected by conventional IVP. Cases studied included 6 renal cell carcinomas, 1 nephroblastoma, 2 transitional cell carcinomas of renal pelvis, 3 parapelvic cysts, 2 polycystic kidneys and 9 other benign renal lesions. CT, especially with enhancement, is advantageous for evaluation of the extent of the tumor and also for the differentiation between cystic and solid masses by their attenuation. However, angiography and venography could provide valuable information for surgery of malignancy; and, retrograde pyelography also would help in assessing the extent of tumor spread in the renal pelvis. Two of our cases of parapelvic cyst and a case of renal bleeding could not be distinguished accurately by CT. Sonography or other diagnostic procedures might be helpful in such cases.