Malignant Solitary Fibrous Tumor of the Renal Vein Presenting as a Giant Renal Artery Aneurysm: A Case Report and Review of Literature

Objectives. To discuss an unusual presentation of solitary fibrous tumor (SFT) as well as the first description of SFT originating from the renal vein. Case Report. In this article, we report the case of a 56-year-old man who presented with nonspecific epigastric pain and was found on computed tomography to have a large 10-cm renal artery aneurysm with evidence of contained rupture, segmental ischemia of the kidney, and suggestion of renal vein thrombosis. This was treated by a multidisciplinary team of urologists, vascular surgeons, and interventional radiologists with both renal artery coil embolization and radical nephrectomy. The thrombosis was found on pathologic review to be a malignant SFT originating from the renal vein with likely erosion into the renal artery. Conclusion. This report describes the first case of SFT originating from the renal vein and demonstrates the potential for mimicry as a giant renal artery aneurysm