CARCINOMA OF THE THYROID MANIFESTED AS HYPERTHYROIDISM CAUSED BY FUNCTIONAL BONE METASTASIS

A rare case of hyperthyroidism in the presence of a functioning bone m etastasis secondary to an occult thyroid cancer is reported, A 59-year -old woman's pelvic bone metastasis was much too extensive and hyperva scular to permit resection, An I-131 scan showed striking activity in the pelvic metastasis, which reflected ectopic excessive production of thyroid hormone by a functioning metastatic thyroid carcinoma. After total thyroidectomy, the patient received I-131 ablation and transcuta neous intra-arterial embolization therapy but her metastasis progressi vely enlarged. Microscopically, concomitant follicular and papillary c ancer was found in close proximity to the thyroid, The patient now has vertebral metastases, and her hyperthyroid state still requires methy mazole to prevent thyrotoxicosis.