The described lesion shows almost most of the typical imaging criteria of the classic adrenal myelolipoma. It is a benign adrenal tumor that is usually incidentally noted with macroscopic fat content. It can be bilateral or unilateral with a right side predilection. It is often hormonally inactive lesion

On CT, the presence of fat densities in a benign looking suprarenal mass lesion is the key for the diagnosis. The non-fatty soft tissue component usually enhances due to hematopoietic tissue composition. 

On MRI, it shows fat suppression and loss of signal on T1 out of phase imaging as the macroscopic fat lacks intracellular water. Rarely, it can cause retroperitoneal hemorrhage. The lesion is usually an admixture of soft tissue and fat, however, it can appear as a complete fatty lesion. 

Other suprarenal neoplasms can show macroscopic fat, but fat-containing malignancies of the adrenal gland are exceedingly rare, like fat-containing adrenal cortical adenoma / carcinoma. Other fat-containing retroperitoneal tumors also could be regarded like lipomas, angiomyolipomas, mature teratomas, and liposarcomas that should be differentiated so. 

Percutaneous fine-needle aspiration by US or CT guidance can confirm the diagnosis.