MEDIASTINAL CYSTIC HYGROMA - REPORT OF 3 CASES AND REVIEW OF THE LITERATURE

Cystic hygromas are benign cysts frequently discovered incidentally on chest X ray films. Although CT scan provides helpful information abou t the size, density, and site of the cysts, it cannot establish a prec ise diagnosis concerning its nature. Complete removal of the cyst is t he treament of choice, and allows precise diagnosis on histological ex amination. However. surgical excision is sometimes difficult, due to t he size end extension of the cysts, infiltrating mediastinal planes, e nveloping great vessels, displacing mediastinal organs without invasio n. The difficulty of completely eradicating certain cysts explains cas es of insidious progression with compressive recurrence.