PULMONARY-ARTERY SARCOMA MIMICKING CHRONIC THROMBOEMBOLIC DISEASE - COMPUTED-TOMOGRAPHY AND MAGNETIC-RESONANCE-IMAGING FINDINGS

Purpose. The diagnosis of the rare primary malignant tumors of the pul monary arteries is often delayed as symptoms are nonspecific. Methods. Computed tomography (CT) and magnetic resonance imaging (MRI) of thre e patients with occlusion of the right pulmonary artery, two with sarc oma and one with chronic thromboembolic disease were analyzed for disc riminating diagnostic criteria. Results. Criteria suggesting pulmonary artery sarcoma are inhomogeneous high or low attenuation (hemorrhage, necrosis), soft-tissue density in pulmonary arteries, vascular disten sion, enhancement after administration of gadopentetate dimeglumine. C riteria for chronic thromboembolic disease are homogeneous soft-tissue lesions, abrupt vascular narrowings and cutoffs, as well as regional parenchymal hyperdensities. Conclusion. CT and MRI provide complementa ry findings suggesting advanced pulmonary artery sarcoma instead of ch ronic thromboembolism.