Primary sarcoma of the pulmonary trunk and/or right or left main pulmonary artery--a rare cause of obstruction to right ventricular outflow. Report on two patients and analysis of 35 previously described patients.

Clinical and morphologic observations are described in two women with primary sarcoma of the pulmonary trunk, and observations in 35 previously described patients with primary sarcoma involving a major extrapulmonary pulmonary artery are summarized. The neoplasm produces symptoms by causing obstruction to right ventricular outflow or by dislodging tumor fragments to the smaller intrapulmonary pulmonary arteries with or without pulmonary infarction. The sarcoma nearly always arises from the pulmonary trunk to which it is firmly attached. Although it grows to a large size within the lumen, it infrequently, despite its highly malignant histologic pattern, extends through the wall of the pulmonary trunk or metastasizes outside the pulmonary circulation. It may mimic a variety of more common disorders. Diagnosis can be achieved by angiography and treatment starts with total excision.