Primary pulmonary artery sarcoma versus pulmonary thromboembolism: a multimodal imaging comparison.

Primary pulmonary artery sarcoma (PPAS) is a rare malignancy that is commonly mistaken for pulmonary embolism due to similarities in clinical presentation and radiographic findings. Distinct radiographic findings to help differentiate between the two diseases are highlighted in the case presented. (1) Several nuances in various imaging modalities have been identified to help distinguish pulmonary artery sarcoma from pulmonary thromboembolic disease. (2) The wall eclipsing sign is considered pathognomonic for pulmonary artery sarcoma. (3) Positron emission tomography/computed tomography may help reduce time between diagnosis and treatment, which may ultimately prolong survival. (4) Providers should be well versed on the subtle differences on imaging to prevent future delays in diagnosis and treatment.