Cervical thymic cysts

Thymic cysts are rarely occurring benign neck masses, most frequently seen in children. They are remnants of the third and fourth branchial pouches. They may occur at any point along the thymic tract, though they have a predilection for the left side of the neck, often deep in the neck. Patients often present with compressive symptoms. Treatment is surgical excision. Care must be taken, however, to confirm the presence of thoracic thymic tissue before excision of this neck lesion. On histology, they are defined by the presence of thymic parenchyma and Hassal corpuscles in the cyst wall.