Thyroid and thymic malignancy following childhood irradiation.

Synchronous thyroid and thymic malignancy following childhood thymic irradiation has only been reported in two known cases previously, with a third case identified here. A rationale is presented for following these radiated patients as they age with thyroglobulin and thyroid-stimulating hormone (TSH) levels as a measure of risk of the development of nodular thyroid disease and, if such occurs, for an aggressive surgical approach. There exists a growing population at risk attributable to the success of radiation treatment of Hodgkin's and pediatric head and neck tumors. The question is raised regarding the theoretical benefits of thyroid suppressive therapy in this group at risk. With the instructive case presented, radical surgery for either thymic or thyroid carcinoma and careful monitoring for decades-late local recurrences of thymoma are suggested.