A case of pulmonary metastatic thyroid cancer complicated with Graves' disease

We report a case of pulmonary metastatic thyroid carcinoma complicated with Graves' disease. A 56-year-old Japanese woman was referred to the Niigata Cancer Center Hospital for isotope therapy for pulmonary metastatic thyroid carcinoma. In 1993, she received a left-hemithyroidectomy. In 1999, the remnant thyroid was resected for isotope therapy of metastatic lesions in the lungs. Although she had been receiving suppressive therapy with levothyroxine, her general condition was good, and TRAb was positive before the operation. After a total thyroidectomy, the patient became thyrotoxic. For functioning metastatic lesions, the patient was treated with 5550 MBq of 131I and methimazole. Thyroid function was normalized after the therapy but TRAb and TSAb levels remained high.