Résumé
We present an 18-year-old male who sought medical attention due to exertional dyspnea of a few weeks' duration. His physical exam revealed an elevated jugular venous pressure, facial puffiness, muffled heart sounds, and mild lower extremity pitting edema. Chest X-ray showed cardiomegaly; and in echocardiography, huge intrapericardial masses with massive pericardial effusion were noted. The oinly noteworthy finding on abdominal ultrasonography and CT scan was the presene of ascites. The only abnormal laboratory results consisted of a hemoglobin level of 10.8 g/dl, a 1-hr ESR 77, CRP 34 mg/dl and LDH 771. Some 1500cc pericardial fluid was aspirated, and tow multilobated creamy-brown masses with foci of necrosis and hemorrhage were excised. Microscopically, hypercellular sheets of malignant round cells were seen. Based on morphology, a diagnosis of high-grade round cell sarcoma was made. Immunohistochemical markers were negative for cytokeratin, CD 34, desmin, and smooth muscle actin, while positive reactivity was noted only for vimentin. Therefore, the cells were mesenchymal in origin with no vascular, skeletal, or smooth muscle differentiation and the final diagnosis was undifferentiated sarcoma. The patient was discharged in good clinical condition and underwent chemoradiation therapy