A unique case of pulmonary artery leiomyosarcoma

Primary pulmonary artery leiomyosarcomas are rare, and the diagnosis is usually confused with other, more common, diseases, especially pulmonary embolism. A 52-year-old male, previously healthy, sustained a cardiac arrest. Chest CT-angiography diagnosed a "saddle embolus." Local thrombolysis was tried without any obvious success. At this point, the possibility of neoplasm was entertained. A cardiac MRI showed a nonhomogeneous mass in the proximal pulmonary artery. Successful surgery was performed, and histological examination of the resected mass was consistent with leiomyosarcoma. A follow-up cardiac MRI showed no residual mass. The dilemma associated with diagnosing pulmonary artery leiomyosarcomas will be discussed.