Right paraspinal retroperitoneal fat containing soft tissue mass. The differential diagnosis includes exophytic renal angiomyolipoma versus retroperitoneal liposarcoma.

The presence of a defect in the right renal parenchyma, other smaller renal parenchymal fat containing nodule (angiomyolipoma), vascular supply from the renal artery as well as a lack of discrete internal enhancing nodules are in keeping with exophytic renal angiomyolipoma.