Pulmonary artery sarcoma mimicking pulmonary embolism: a case series

Background: Pulmonary artery sarcoma (PAS) is a rare malignant neoplasm with an aggressive behavior and often difficult to distinguish from pulmonary thromboembolic disease. Aim: To assess the demographic, clinical, and radiological characteristics of PAS and clinical course. Design and Methods: We retrospectively identified and analyzed all patients with PAS seen at Mayo Clinic in Rochester, Minnesota, between January 1, 1996 and July 31, 2015. Results: Of nine patients (5 women and 4 men; median age 55 years [range, 24-74 years]), eight were diagnosed while alive with surgical (n = 6) or catheter-based endovascular biopsy (n = 2); the remaining patient was diagnosed at postmortem examination. All tumors manifested on CT as filling defect in the main, right or left pulmonary artery and were not associated with peripheral filling defects in seven patients. Seven patients were initially treated with anticoagulant therapy for presumed PE; two patients were suspected to have tumor based on constrictive or expanding effect seen on CT. Five patients died after a mean duration of 2.1 years (10 months-4.25 years) after diagnosis. Two patients are alive with recurrence and metastases of the disease 23 and 27 months after diagnosis, respectively; one remaining patient is alive and disease-free 116 months after diagnosis. Conclusions: Although PAS is associated with a poor prognosis, long-term survival is possible and can be improved by early diagnosis and prompt surgical resection. Atypical appearance on CT including central mass-like lesion without peripheral emboli and constrictive or expanding effect should raise suspicion of PAS.