A case of hypervascular renal capsule leiomyoma

A case of leiomyoma of the kidney is reported. A 54-year-old woman was found incidentally to have a solid left renal mass on abdominal ultrasound examination performed during a follow-up study for chronic hepatitis, type C. Computed tomography (CT), dynamic magnetic resonance imaging (MRI), and angiography revealed the hypervascular mass. Partial nephrectomy was performed under a preoperative diagnosis of renal cell carcinoma. Histopathology diagnosed the mass as renal capsular leiomyoma. We considered that the hypervascularity of the tumor was related to the presence of rich capillary beds.