[A case of renal hemangiopericytoma].

The patient is a 33-year-old female. On precontrast CT, the tumor shows a high density area with a low density area. On postcontrast CT, the tumor demonstrates a well-marginated low density area. Angiographically, the tumor shows a hypervascular mass with tumor vessels like a weeping willow and unhomogeneous stain. This is only the fourth such case ever reported before in Japan.