Cervical presentation of thymic cysts.

Sixteen cases of cervical thymic cyst are added to the previously reported fifty-six cases. Seventy-five per cent of the patients were less than twenty years old. Eighty per cent complained of a painless mass preoperatively. The histologic diagnosis of cervical thymic cyst was made if thymic epithelial elements could be found adjacent to the cyst cavity; Hassall's corpuscles were usually present. Cholesterol granulomata could usually be identified. The theories of origin of cervical thymic cyst are discussed.