[Two cases of surgically treated malignant primary tumors originated from the pulmonary artery].

Two surgically treated cases of malignant tumors which originated inside of the pulmonary artery were reported. A 62-year-old female with an undifferentiated sarcoma and a 24-year-old male with a malignant fibrous histiocytoma were successively operated on in two months for the release of their chief complaints of exertional dyspnea. In the first case the tumor was resected completely, although partially resected in the second case. Preoperatively, noninvasive examinations including the echocardiography, the computed tomography and the magnetic resonance imaging confirmed the presence of these tumors in the main pulmonary arteries in both cases and also the invasion to the vessel wall with the growth to the pericardial cavity in the second case. Both patients are doing well and has been followed up at the out-patient department 22 and 20 months after surgery, respectively.