Successful resection of a retroperitoneal malignant fibrous histiocytoma with caval tumor thrombus.

We report herein the case of a 56-year-old man who presented with a huge, fast-growing abdominal tumor. Renal angiograms revealed a hypervascular tumor stain from the renal capsular arteries, and magnetic resonance imaging revealed a caval tumor thrombus. The tumor was resected en bloc with the tumor thrombus, the right kidney, and part of the liver. The histological diagnosis confirmed malignant fibrous histiocytoma (MFH) both in the tumor and the caval tumor thrombus. This is the first report of the successful resection of a MFH originating in the renal capsular tissue and extending into the inferior vena cava.