Hyaline vascular-type Castleman disease: a rare cause of a hypervascular retroperitoneal mass.

We present the cross-sectional imaging and angiographic findings of hyaline vascular-type Castleman disease located in the retroperitoneum. The diagnosis was made postoperatively. This entity can simulate a malignant neoplasm. The histologic subtypes and presentations of Castleman disease and the differential diagnosis of retroperitoneal masses are discussed.