New classification of renal angiomyolipoma

Angiomyolipoma (AML) is the most common benign solid renal neoplasm observed in clinical practice. Once thought to be a hamartoma, this neoplasm now considered among the family of PEComa. We recently provided a new radiological classification of AMLs that helps physicians understand the recent development and variety of its pathology, imaging features and its management. AMLs are divided into triphasic benign AML and epithelioid AML with malignant potential. Triphasic benign AMLs are consisted of classic AML which can be diagnosed by the detection of fat on imaging, and fat poor AML which can not. A hyperat-tenuating appearance on unenhanced CT and a T2-hypointense appearance at MRI both correspond to the smooth muscle component, are important diagnostic clues to the types of AMLs that contain few or no fat cells.