[A case of primary pulmonary artery sarcoma].

A 39-year-old male was admitted with persistent cough, palpitations and dyspnea on exertion. Chest X-ray showed cardiomegaly, left pleural effusion and left hilar mass shadow. Echocardiogram revealed dilatation and hypertrophy of the right atrium and ventricle. Perfusion lung scintigram disclosed a complete defect of the left lung and a partial defect of the right upper lobe. CT scan showed an intravascular tumor mass in the bilateral main pulmonary arteries. Digital subtraction angiography of the pulmonary artery revealed complete obstruction of the left pulmonary artery and stenosis of the right pulmonary artery. MR image showed intravascular tumor infiltrating the mediastinum and surrounding tissue. Sarcoma was highly suspected, but a histopathological diagnosis could not be made. The patient died of heart failure two months after admission to our hospital. Postmortem examination showed that the pulmonary trunk and left main pulmonary artery were markedly dilated and completely occluded by the tumor. Tumor infiltrated into the left upper lobe and mediastinal lymph nodes. The tumor was histologically diagnosed as undifferentiated sarcoma.