Imaging findings. (A) Ultrasound image showing a heterogeneous mass (*) in the upper pole of the left kidney (LK). (B) Axial T1-weighted and (C) coronal T2-weighted imaging demonstrating a mass in the left kidney (*), with homogeneous low T1 and a high signal in T2. A central scar (arrow) is seen on axial T1. (D) Axial T1, postcontrast, showing a hypovascular lesion compared to renal cortex (white arrow) with a central scar (*). (E) Gross findings: well-circumscribed tumor with a central scar (arrow). (F) Elongated tubules and cord arrangements (arrows) embedded in a mucinous stroma (*). LK, left kidney.