Tumors of the pulmonary artery and veins.

The pulmonary vasculature may be involved by different primary and secondary tumors. Poorly differentiated and undifferentiated sarcomas are the most common primary tumors of the pulmonary arteries. They tend to affect the large caliber pulmonary vessels and present with predominantly intraluminal growth. Pulmonary and mediastinal metastasis are common, and prognosis is poor. Clinical and imaging manifestations may mimic those of pulmonary embolism. Dyspnea, chest pain, cough, and hemoptysis are the most common presenting symptoms. Primary sarcomas arising from the central pulmonary veins are less common than their arterial counterpart. Secondary involvement of the pulmonary arteries and veins by primary and metastatic pulmonary malignancies is more common. Tumoral embolism may also affect the pulmonary arteries. They may develop from different intrathoracic and extrathoracic malignancies and may be indistinguishable from venous thromboembolism. It may manifest as cor pulmonale with right cardiac strain and dilated pulmonary arteries. Computed tomography, magnetic resonance imaging, and fluorodeoxyglucose positron emission tomography may help in the differentiation between these 2 conditions.