Incidental finding of right renal venous aneurysm in a patient with symptomatic ipsilateral renal carcinoma: a case report.

Abstract Background True venous aneurysms of the renal veins are very uncommon lesions. Diagnosis is incidental, and thrombosed aneurysms may simulate solid renal masses. Methods and Results A case of right renal vein aneurysm incidentally found in a patient with a ispilateral renal carcinoma and abdominal aortic aneurysm is reported. While CT examination suggested a high-flow arteriovenous (A-V) malformation, a selective angiographic study identified two separate and independent pathologic conditions (venous aneurysm and intratumoral, acquired A-V fistulae). Successful preoperative embolization of the renal tumor was obtained and surgical treatment (nephrectomy+aneurysmectomy) was uneventful. Conclusions Although uncommon, venous renal aneurysms require an accurate preoperative diagnosis; this case is interesting because the coexistence of renal tumor with acquired A-V fistulae raised the prospect of a large, high-flow A-V communication with secondary venous enlargement. The integrated imaging studies were basic to differentiate acquired, tumor-induced A-V fistulae found in the lower renal pole from the true venous aneurysm located in the upper pole. To our knowledge, this is the first report of such a condition.