Renal angiomyolipoma.

• Renal angiomyolipomas (AMLs) are usually easy to diagnose with imaging alone. They have unique characteristics on ultrasonography, computerised tomography and magnetic resonance imaging that usually allow AMLs to be differentiated from other renal masses. • If this is not possible on imaging criteria then biopsy can be performed and AMLs have unique immunohistochemical staining that allows them to be accurately differentiated from other renal tumours.