While most of hygromas in the neck or lower face occur in the pediatric age group, isolated mediastinal lesions occur more commonly in adults.
Most Patients are asymptomatic.
A mass is first detected on routine chest radiograph. Pain may result from hemorrhage or infection in the cystic structures. Dyspnea may result from compression of major airway. Although lymphangioma is a benign tumor, its infiltrative tendency sometimes makes complete removal difficult and results in a high recurrence rate postoperatively. Lymphangiomas are tumor like congenital anomalies or hamartomatous changes consisting of endothelial-lined spaces that can vary from capillary size to several centimeters in diameter.