Contrast

Renal oncocytomas are uncommon, benign tumors that can be treated by local excision or heminephrectomy; their preoperative differentiation from renal cell carcinoma, treated by radical nephrectomy, would be invaluable. A particularly important finding, a central scar--not stressed in previous reports, is frequently demonstrated by CT examination. We evaluated radiographic studies of 18 pathologically confirmed cases of oncocytoma and compared findings with results of CT, sonography, and angiography studies of 18 renal cell carcinoma cases. Oncocytomas can be suggested if a stellate scar is identified within an otherwise homogenous tumor on ultrasound (US) and CT; if the mass appears homogeneous but no scar is present, angiography should be performed. An oncocytoma can be suggested in these cases if a spoke-wheel configuration and homogeneous blush are present. These criteria, which are reliable only if the mass is 3 cm or larger, would have resulted in the correct diagnosis of oncocytoma in 16/18 cases.

Computed tomographic (CT) scans of 34 cases of abdominal fatty masses were reviewed retrospectively in order to establish criteria for distinguishing benign conditions from malignant tumors. By evaluating location, attenuation, internal consistency, and margination, it is possible not only to make this distinction but frequently to suggest a specific diagnosis. Abdominal fatty masses that are sharply marginated, homogeneous, and that show CT numbers less than or equal to the patient's normal fat can be considered benign. Malignancy should be suspected when an extrarenal abdominal fatty mass displays one or more of the following characteristics: inhomogeneity, infiltration or poor margination, CT numbers greater than the patient's normal fat, or contrast enhancement. Criteria for distinguishing between angiomyolipoma and liposarcoma are also discussed.

No abstract

L3 vertebral body were noted. The IVC was considered to be lateral to the L3 vertebral body 0361-803X/88/1503-0591 if more than 50% of the volume of the IVC was lateral to the lateral margin of the right