Metastatic pulmonary artery sarcoma. Report of a case with diagnosis by fine needle aspiration

Primary pulmonary artery sarcomas (PPASs) are uncommon neoplasms with a poor prognosis. They often present with symptoms of pulmonary thromboembolus. They may be locally aggressive and give rise to embolic pulmonary metastases. Extrathoracic metastases are uncommon. They are usually diagnosed late in the course of the disease or at autopsy. Radiographic studies alone are insufficient to definitively diagnose PPAS.

A 68-year-old female presented with symptoms consistent with pulmonary thromboemboli. Computed tomography of the chest with intravenous contrast revealed an intraluminal filling defect involving the left main pulmonary artery. Despite anticoagulation therapy, the symptoms persisted. Four months after the initial presentation, the patient developed multiple nodules in the left lung. Fine needle aspiration (FNA) of one of the nodules showed loosely cohesive clusters of pleomorphic and spindle-shaped malignant cells and isolated ones. These cells were embedded in extracellular, metachromatic material. They were vimentin positive and keratin negative. There was no evidence of extrapulmonary disease. A diagnosis of metastatic pulmonary artery sarcoma was made and confirmed on histology. Three weeks following the pneumonectomy, the patient died of postoperative complications.

Patients with PPAS often present with symptoms of atypical or nonresolving pulmonary thromboemboli. The interval between presentation and definitive diagnosis is usually delayed and probably affects the prognosis. The timely use of FNA techniques could result in an earlier diagnosis, possibly improving outcome.