Thoracic duct cyst in posterior mediatinum, surrounding thoracic aorta and azygos vein ; a case report

Abstract

A 19-year-old male was admitted with an abnormal shadow in his chest roentgenogram, which appeared to be a mediastinal mass. CT scan, endoscopic ultrasonography and MRI showed a cystic lesion surrounding the aorta and azygos vein. Other laboratory data were within normal limits.
Thoracotomy was performed without a preoperative diagnosis. The cyst, 8 × 5 × 11cm in size, was located in the posterior mediastinum. The thoracic duct and cyst were in contact, and there was a pin-hole communication between them. The fluid in the cyst was bloody and chylous. So, the diagnosis was thoracic duct cyst. Twenty-five thoracic duct cysts in the mediastinum have been reported. However, none surrounded the thoracic aorta and azygos vein, as it did in this case.