Cervical thymic cyst: case reports and review of the literature.

Due to its rarity, cervical thymic cyst is seldom included in the differential diagnosis of a neck mass. Approximately 80 cases have been reported thus far, and most of these cases have occurred asymptomatically in children and adults. Only 5 cases have involved patients younger than 1 year of age. The authors report four new patients with thymic cyst in the neck. Two of the patients were newborns in whom the cyst caused airway obstruction and dysphagia. All four patients underwent successful resection of the lesions, with complete resolution of symptoms. The embryology, histopathology, and differential diagnosis of cervical thymic cysts are also reviewed. The authors recommend that despite its infrequent occurrence cervical thymic cyst should be considered in the evaluation of neck masses in children.