[A case of renal capsular leiomyoma]

A 50-year-old woman was admitted for the treatment of retroperitoneal tumor. Enhanced comtuted tomography showed a low density mass between the left kidney and psoas muscle. Magnetic resonance imaging revealed a high intensity and homogeneous mass on T1-weighted sequence, and a low intensity and heterogeneous mass on T2-weighted sequence. Surgical exploration revealed that the tumor was adherent to the left kidney and en bloc excision of the tumor and the left kidney was performed. Histopathological diagnosis was leiomyoma originating from the renal capsule.