Uncommon Childhood Unilateral Cervical Giant Thymic Cyst.

Cervical thymic cysts are rare and present in the first decade of life. They constitute 0.3% to 1% of congenital neck masses. Thymic tissue foci, which exist between the mandible and the mediastinum, can be found at the descent of the thymic primordium. Thymic cysts should be considered in pediatric patients who present with cervical neck masses. The diagnosis of thymic cysts can only be made by histopathologic examinations. In recent years, the number of reports of thymic cyst cases have increased, one possible cause being the heightened awareness of thymic cysts among pathologists.