[A case of malignant fibrous histiocytoma in the mediastinum].

A 81-year-old man was admitted to the hospital because he complained of hoarseness. Chest radiography showed a mass in the right upper mediastinum. An operation was done to remove the mass and make a conclusive diagnosis. Histologically, the tumor tissue consisted of spindle-shaped fibroblast-like cells and round histiocyte-like cells with bizarre giant cells. Part of the tissue had a storiform pattern. These findings led a diagnosis of malignant fibrous histiocytoma (MFH) of the "usual type". MFH is known to occur frequently in the soft tissues of extremities, trunk, and retroperitoneum, but it is seldom detected in the mediastinum. We report here a rare case of primary MFH in the mediastinum.