A 60-year-old woman was found to have a pericardial mass on two-dimens
ional echocardiography and computerized tomography. At autopsy, there
was a large tumor arising from the epicardial surface of the left vent
ricle. The tumor encircled the great arteries and invaded the wall of
the pulmonary artery. Microscopic examination showed features of an un
differentiated sarcoma.