Solitary Pulmonary Artery Intima Sarcoma Manifesting as Pulmonary Embolism and Subacute Cor Pulmonale
A 47-year-old previously healthy man presenting with progressive shortness of breath, hemoptysis, and near-syncope visited our emergency department. On physical examination, the patient was in respiratory distress, with tachypnea (28 breaths per minute), blood pressure of 137/83 mm Hg, and pulse rate of 114 bpm. Cardiac auscultation revealed a loud P2 and a grade III/VI systolic murmur over the left sternal border. ECG showed sinus tachycardia, P-wave pulmonale, and a S1Q3T3 pattern. A contrast-enhanced spiral computed tomographic scan showed massive filling defects over the main pulmonary trunk and bilateral proximal pulmonary arteries (Figure 1). Echocardiography demonstrated a dilated right atrium and right ventricle (Figure 2). Systolic pulmonary artery pressure estimated by tricuspid regurgitation jet velocity was 100 mm Hg (Figure 3). Venous duplex examination for deep vein thrombosis was negative. Surveys for coagulopathy, including anticardiolipin antibody, D-dimer, fragment degradation product, and protamine sulfate time, were normal.
Parenteral anticoagulation with unfractionated heparin was initiated. Because of worsened dyspnea and right ventricular dysfunction, thrombolytic therapy was used thereafter. Then emergent pulmonary thromboendarterectomy was performed because of progressive hypoxemia and hemodynamic instability. A 7×3×2-cm, yellowish, phylloid, and fragile mass lesion was found in main pulmonary trunk and bilateral proximal pulmonary arteries. Pathology of the tumor specimen revealed pulmonary artery intima sarcoma (Figure 4).
Pulmonary artery intima sarcoma and pulmonary embolism are challenging diseases that both appear as intraluminal filling defects in the pulmonary artery system on contrast-enhanced computed tomographic scans. Although pulmonary artery intima sarcoma, which was first described by Mandelstamm in 1923,1 is rare, it is important to keep in mind when formulating the differential diagnosis for patients with symptoms and signs of pulmonary artery disease, in particular if they have image findings that are not entirely consistent with thromboembolic disease. For example, defects that occupy the entire luminal diameter of the main or proximal pulmonary artery, extraluminal expansion of the defect beyond the artery, and expansion of the artery with the defect, as shown in this case, are more consistent with malignancy.2 In addition, normal coagulation parameters were quite unusual for pulmonary embolism. The differentiation of these 2 diseases is fundamental to avoid inappropriate therapy, such as prolonged anticoagulation. The survival of patients with pulmonary artery intima sarcoma can be prolonged if the tumor is diagnosed early and if multimodality treatment, including radical surgical resection and chemotherapy and radiotherapy, is performed.