Pulmonary artery leiomyosarcoma with thyroid metastases.

Primary pulmonary artery sarcomas are uncommon and usually fatal tumours. The diagnosis of these tumours is delayed in most cases as they are mistaken for pulmonary thromboembolism. We present a fatal case of a woman referred to us five months after a primary diagnosis of pulmonary thromboembolism, due to an increase in dyspnea and presence of hemoptysis despite having undergone anticoagulant treatment. On the basis of the findings obtained by computed tomography, echocardiogram and MRI, a mass arising from the pulmonary trunk was evidenced, that suggested other diagnostic hypotheses. The worsening of patient's conditions did not allow an endovascular catheter biopsy and diagnosis was made at autopsy. The mass was a leiomyosarcoma of the pulmonary artery with thyroid metastases, which is an uncommon findings.