Controversies in thyroid surgery

Abstract

Especially in adults there is doubt as to whether radiation of the thyroid for benign disease causes a significant increase in the incidence of cancer of the thyroid. Certainly the risk would not be enough to warrant the routine use of scanning; a test which in the absence of thyroid nodules is highly inaccurate, and in the presence of nodules unnecessary. Although there is no definite limit to the incubation period of cancer following radiation to the thyroid, it seems that most clinical cancers occur from 5 to 20 years after exposure. Most of the cancers discovered later than that have been inconsequential, occult, or in situ lesions found by accident in operations performed for other reasons. After radiation it is chiefly the occult or in situ cancer of the thyroid that is increased. The presence of these cancers does not threaten life, and the growth of almost all of them can be controlled by feeding suppressive doses of thyroid. The rare, clinical evidence of papillary cancer of the thyroid that occurs following radiation is highly curable by total lobectomy on the affected side, with removal of the isthmus and most of the contralateral lobe. Total thyroidectomy should be used only when there is diffuse bilateral involvement. After operation, suppression by feeding thyroid is simpler and more effective in controlling recurrences than is administration of radioactive iodine.