Pulmonary Artery Intimal Sarcoma: Diagnostic and Surgical Strategy from a Rare Case

Pulmonary artery intimal sarcoma (PAIS) is a rare tumor, and the prognosis is extremely poor. Radical surgery for PAIS is the best option for prolonging survival. Thus, PAIS should be diagnosed as soon as possible, and radical surgery should be performed rapidly. However, it is difficult to differentiate PAIS from pulmonary embolism in the early stage. We report the case of a patient who was diagnosed with PAIS by endovascular catheter biopsy in the early period and who underwent left pneumonectomy, accompanied by resection of the main and right pulmonary arteries and right pulmonary artery reconstruction via median sternotomy for radical surgery.

A 53-year-old man presented to cardiologists for dyspnea. Contrast-enhanced CT revealed an occlusive mass in the left and main pulmonary arteries. The cardiologists diagnosed the patient with pulmonary embolism and started administering an anticoagulant. However, the mass did not shrink, and the cardiologist consulted the cardiovascular surgeons. A cardiologist performed an endovascular catheter biopsy to differentiate between the thrombus and the tumor. The biopsy specimen tissue contained atypical cells and was negative for Mouse Double Minute protein 2. The surgery was performed via median sternotomy. Cardiopulmonary bypass was established. The tumor filled the left pulmonary artery and extended to the main and right pulmonary arteries. With sufficient margins from the tumor, the main and right pulmonary arteries were resected and subjected to rapid intraoperative pathological diagnosis, with positive margins of the main pulmonary artery. Additional resection just above the pulmonary artery valve and reconstruction of the right pulmonary artery were performed, followed by left pneumonectomy. The postoperative histological diagnosis of the tumor was PAIS. The surgical margin of the main pulmonary artery was microscopically positive for tumor cells. Chemoradiotherapy was started postoperatively. There was no recurrence in the pulmonary artery, but a head MRI revealed a metastatic brain tumor, and the patient died approximately 1.5 years after surgery.

Endovascular catheter biopsies are useful for differentiating thrombi from tumors. Furthermore, an early diagnosis of PAIS is important to ensure adequate time for discussing the surgical strategy with thoracic surgeons.