There was coexistence of thyroid carcinoma and hyperthyroidism in a 37-year-old woman previously (apparently successfully) treated with sodium iodide I 131 for thyrotoxicosis. There was an uncommon sequence of events in this case and a possible relationship between131I therapy and subsequent development of thyroid carcinoma existed. Since the reported frequency of thyroid carcinoma following131I therapy in the adult is well within the range of statistical coincidence, no basis for a cause and effect relationship presently exists.
Burke G, Levinson MJ, Zitman IH. Thyroid Carcinoma Ten Years After Sodium Iodide I131 Treatment. JAMA. 1967;199(4):247-251. doi:10.1001/jama.1967.03120040057009