Malignant fibrous histiocytoma of the heart presenting as unilateral pulmonary thromboembolism and infarct.

A malignant fibrous histiocytoma of the heart located at the pulmonic valve and thrombotic occlusion of branches of the left pulmonary artery with pulmonary infarct were found at autopsy in a 77-year-old man. The thrombi contained malignant cells. The patient had undergone left upper lobectomy four years earlier for thromboembolism with infarct, and review of the slides from that procedure revealed similar malignant cells within thrombi. This case is remarkable for the slow growth of the neoplasm and the prolonged survival of the patient, without specific therapy.