A 50-year-old patient had been having recurrent headaches, and right upper and lower extremity weakness, which was worked up. Thoracic surgery was consulted after finding a 4.3
8.7-cm mass in the antero-superior mediastinum; see Figure . It was located between the origins of the left subclavian and left common carotid arteries, displacing without compressing both vessels. It extended as cephalad as the left lobe of the thyroid gland. It was causing compression of the left brachiocephalic and left internal jugular veins. No other masses or cervical adenopathy was noted. Urine levels of epinephrine, norepinephrine, VMA, metanephrine and normetanephrine were within normal limits.
Angiographic image of the mediastinal mass.
A CT-guided biopsy of the mediastinal mass was performed using a 19-gauge needle. No complications were encountered. Pathologic examination revealed findings typical of a paraganglioma. Nests of cells with uniform bland nuclei and abundant pink granular cytoplasm in an organoid pattern were seen. Chromogranin and S-100 staining of the sustentacular cells was strongly positive.
An interventional radiology consultation was obtained for an angiogram and possible embolization before undertaking surgical resection of the tumor. This revealed the proximal great vessels were widely patent without significant luminal irregularity or stenosis. However, there was a mild mass effect with splaying of proximal left common carotid and left subclavian arteries by the underlying mass. Two main branches of the left thyrocervical trunk were supplying the large hypervascular mass in the left cervical region extending to the aortic arch. The tumor demonstrated marked hypervascularity with multiple dilated and ectatic outflow veins. There was another small arterial branch arising from left inferior thyroidal artery. Selective embolization of the two main feeding vessels from the left thyrocervical trunk was performed. There was minimal vascularity of the tumor following embolotherapy.
The patient was taken to the operating room 24
h later for definitive resection using median sternotomy. The tumor originated between the left subclavian and left common carotid arteries. It was sharply dissected away from the mediastinal pleura, but the pleural cavity was entered. It was dissected from the pericardium and great vessels with relative ease without major blood loss. Although we were ready for the possibility, cardiopulmonary bypass was not needed. The tumor extended along the left common carotid and internal jugular veins into the neck, with an anatomic plane allowing safe dissection. Final pathology revealed an encapsulated paraganglioma. Hemostasis was adequate, and there no major intraoperative or postoperative bleeding problems. Our patient had an uneventful postoperative recovery and continues to do well 6