Abstract
We report a case of follicular thyroid carcinoma with bone metastases showing TRAb-positive hyperthyroidism after total thyroidectomy. A 58-year-old woman noticing a left scapular tumor was found in pathological studies to have bone metastasis from follicular thyroid carcinoma, necessitating total thyroidectomy in September 2003. Her serum fT3 and fT4 were slightly high (fT3 9.3 pg/ml: normal 2.2-4.1, fT4 1.8 ng/dl: 0.8-1.9) taking levothyroxine at 100 μg/day when discharged. These gradually rose despite total thyroidectomy. Her serum TRAb was positive (26.7%: normal 0-10%) in October, so we considered that she has functional bone metastases with Graves' disease and prescribed thiamazole at 10 mg/day. Her TRAb remained high (31.8%), but thyroid function fell to within normal limits and the scapular metastatic tumor shrank slightly after therapy.
