Radiation-associated thyroid carcinoma

Abstract

Since February, 1977, 735 patients having a history of receiving radiation therapy for benign conditions of the head and neck areas during infancy and childhood were examined in a thyroid screening program, and 159 patients were found to have palpable thyroid nodules. These patients had thyroid function tests and indirect laryngoscopy and were followed closely on suppression therapy consisting of either Cytomel or thyroid extract. Thyroidectomy was advised in those in whom the nodules persisted or increased in size. This study documents the incidence of carcinoma and other benign pathological changes and postoperative complications in this group of patients. So far, 49 patients had either a lobectomy with isthmusectomy or a total thyroidectomy. Eleven patients were found to have carcinoma (six had papillary, four had mixed papillary and follicular, and one had follicular carcinoma). Three patients had a therapeutic modified neck dissection following the documentation of microscopic involvement of paratracheal lymph nodes. A high incidence of chronic nonspecific thyroiditis, postradiation fibrosis, and follicular adenomas were also found in these patients. Three patients had temporary hypocalcemia (two weeks) and none had wound infection, hematoma, or postoperative nerve palsy. Of patients who had surgical resection, 22.4% showed thyroid carcinoma.