A Renal Angiomyolipoma with a Challenging Presentation: a Case Report

Introduction Renal angiomyolipoma is considered a benign mesenchymal tumor composed of fat, smooth muscle, and blood vessels. It represents 1-3% of solid renal tumors. Despite this tumor's benignity, it can be aggressive with a locoregional extension. Case report A 41-year-old north African caucasian woman consulted with chief complaints of right lower back pain with no hematuria and no urinal sign. Thoracic-abdominopelvic contrast-enhanced computed tomography showed a right inferior polar heterogeneous renal mass complicated with venous thrombus ascending to the right atrium level. The patient underwent radical nephrectomy under extracorporeal circulation and direct supervision of the fatty thrombus at the right atrium level. The postoperative period was uneventful. The final histologic examination was concordant with renal angiomyolipoma. Conclusion Renal angiomyolipoma is the most common benign kidney tumor. Despite its benignity, it can be associated with lethal complications such as hemorrhage, and it can also show signs of local extension mimicking malignant tumors. The cornerstone of the treatment remains surgery.