Beyond Clots in the Pulmonary Circulation

Pulmonary embolism (PE) is the most common filling defect seen on CT scan pulmonary angiography. Pulmonary artery (PA) tumors can mimic PE on imaging and clinical presentation. One classic feature of tumors is failure to improve on anticoagulation. PA tumors, particularly malignant ones, have radically different treatments and usually have a grim prognosis. Thus, it is essential that PA tumors, when suspected, receive an expedited confirmatory diagnosis followed by multidisciplinary treatment at an expert center. In this review, we present clinical, imaging, and histopathologic features of benign and malignant PA tumors, emphasizing differentiating features from PE. We also describe available diagnostic and treatment methods for PA tumors.