Malignant fibrous histiocytoma of the mediastinum and lung: a report of three cases.

One case of primary malignant fibrous histiocytoma of the lung and two cases of that tumor in the mediastinum are reported. Primary malignant fibrous histiocytoma is rare in those areas, appearing more commonly in deep fascia and skeletal muscles of the extremities and torso and in the retroperitoneum. Most of the tumors contain both fibroblast-like and histiocyte-like cells; some contain pleomorphic giant cells and inflammatory cells. They are often confused with other sarcomas, and their true biologic potential is not clearly defined. Radiation appears to be a very useful adjunct to surgical therapy and was used in the cases reported here.