Computed tomographic evaluation of intrathoracic thyroid malignancy.

As only a few cases of intrathoracic thyroid malignancy with computed tomographic (CT) examination have been described, we reviewed the CT examinations of three patients with primary and five patients with recurrent thyroid malignancy involving the thorax. Irregular border of the thyroid mass, extension of tumor mass into mediastinal fat or chest wall, or lymphadenopathy suggested the malignant nature of the primary tumor. CT examination in recurrent disease demonstrated mediastinal, hilar and retrocrural adenopathy, compression of major vessels with collateral flow, pulmonary and bony metastases. CT was of value both in identifying the extent of disease and documenting response to treatment.