Malignant fibrous histiocytoma in thoracic surgical practice.

Malignant fibrous histiocytoma is a rare, although increasingly recognized, deep-seated pleomorphic sarcoma. A primitive tumor, it arises from tissue histiocytes and typically occurs in the extremities. Primary intrathoracic tumors have been reported rarely. The presentation of malignant fibrous histiocytoma in our series of seven patients has been varied. Two cases presented as solitary primary intrapulmonary tumors, two as primary chest wall tumors, one as an anterior mediastinal mass, one as a retroperitoneal tumor extending cephalad through the diaphragm, and one as a late metastasis from a primary pelvic site. Malignant fibrous histiocytoma is aggressive, with a propensity for early local and distant spread; three of the patients in our series died of progressive disease within 17 months of operation. The histologic nature of the tumor makes diagnosis on small biopsy specimens difficult and frequently misleading. We would suggest a policy of open biopsy to obtain adequate and representative specimens for histologic study and preoperative computed tomographic scanning to augment the clinical search for metastatic disease and to facilitate planning of subsequent radical, excisional operation. The preoperative use of deep x-ray therapy or the newer chemotherapeutic agents may reduce tumor bulk and thereby facilitate radical operation, which presently appears to be the most appropriate primary modality of treatment of malignant fibrous histiocytoma.