Primary pericardial mesothelioma demonstrated by magnetic resonance imaging.

A 24-year-old man was hospitalized for an investigation of cardiac enlargement. Serum hyaluronic acid was increased to 238 ng/ml. Echocardiogram showed pericardial effusion with an area of increased density adjacent to the anterolateral wall of the left ventricle. A soft-tissue mass within the pericardial space was enhanced with gadolinium DTPA on magnetic resonance imaging. Open biopsy confirmed the presence of a malignant mesothelioma. Magnetic resonance imaging provided useful information regarding the tumor.