Thyroid Carcinoma After Irradiation

Abstract

External irradiation to the head and neck has been indicated as a causative factor of thyroid carcinoma since 1950, when Duffy and Fitzgerald¹ reported on 28 children who developed thyroid carcinoma; ten of the children had received prior irradiation. The late Dwight E. Clark in 1955² published a series comprised of 15 children whom he treated for carcinoma of the thyroid arising subsequent to irradiation of the head and neck. The association of thyroid carcinoma following irradiation to the head and neck was studied extensively by Simpson and Hampelman.³ After following 1,400 children who had received such irradiation, he found that six developed a thyroid carcinoma and nine developed a thyroid adenoma. He also followed 1,795 unirradiated sibling controls and found no thyroid disease. The natural incidence of thyroid carcinoma in persons under 25 years of age is approximately four per million man-years at risk.⁴ Beach