Pulmonary artery sarcoma mimicking a pulmonary embolism

Abstract

27ordered by his primary physician, showed extension of the clot, accompanied this time by the appearance of lung nodules [ Figure 1]. He was recommended discontinuation of warfarin and to be evaluated in hematology/oncology to rule out a neoplastic process.When seen at our institution, his only complaint was ongoing exertional shortness of breath, with no associated hemoptysis, chest pain, cough, night sweats or loss of consciousness. His review of systems was otherwise non-contributory. On account of the suspicion of a possible neoplastic process, a PET scan was obtained, which revealed increased radiotracer uptake over the area of the presumed pulmonary thrombus, as well as other areas of the right lung, including a lower lobe sub pleural nodule [ Figure 2].During his outpatient evaluation he developed two syncopal episodes, with associated exertional dyspnea and presented to our Emergency Department. His electrocardiogram showed ST elevations in leads V3-V5 along with a small elevation in the troponin I of 0.31 (normal is less than 0.20), indicative of AbstractSarcomas involving the lung are a rare occurrence, often a result of metastatic disease from primary malignancies involving the skin, liver, breast or heart. Primary pulmonary artery sarcomas are rarer still, with limited cases reported world-wide and consequently data regarding treatment modalities are sparse and largely experimental. These tumors are often mistaken for a pulmonary embolism and seemingly supported by radiological fi ndings. Patients will often present without symptom resolution despite therapeutic anticoagulation. The following case illustrates how a soft tissue sarcoma of the pulmonary artery can mimic a pulmonary embolism, thus, resulting in both a diagnostic and therapeutic dilemma. A positron emission tomography scan was an invaluable tool in this case, showing increased radiotracer uptake and placing neoplasm at the top of the differential diagnosis. This ultimately led to a biopsy that was vimentin positive, cytokeratin negative and CD117 negative, thus consistent with soft tissue sarcoma.