There are numerous fat-containing renal lesions, including:
renal cell carcinoma (often has calcifications when contains macroscopic fat)
Wilms tumor (most common pediatric renal mass)
renal or perirenal lipoma/liposarcoma
Non-mass lesions may also occasionally contain fat:
fat in a renal scar
Practical points
Fat-containing lesions in the perinephric space may also mimic a fat-containing renal lesion, including:
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