Renal oncocytoma. Further diagnostic observations.

Radiographic findings of the 2 new cases of oxyphilic renal adenoma, so-called renal oncocytoma, are reported and compared to previous descriptions. Ultrasonography shows no typical findings, but the vascular capsule of this tumor may show enhancement on computed tomography. Angiography contributes the most specific findings, because of the vascularity of these tumors: In the larger lesions a typical 'spoke wheel pattern' can be expected which may not be as prominent in smaller tumors. Notable is the absence of abrupt arterial caliber changes, AV shunting and contrast puddling which sets this tumor apart from the great majority of vascular renal cell carcinomas. The incidence of renal oncocytomas appears to be rising.