Comparison of Administration of Recombinant Human Thyrotropin with Withdrawal of Thyroid Hormone for Radioactive Iodine Scanning in Patients with Thyroid Carcinoma

Thyroid carcinoma is diagnosed in 14,000 people each year in the United States. 1 Most are effectively treated by surgery, followed often by radioiodine therapy and always by thyroid hormone therapy to suppress the secretion of thyrotropin. These patients require monitoring for recurrence of tumor, which can occur decades later. 2 , 3 In some patients, monitoring includes periodic discontinuation of thyroid hormone therapy for radioiodine scanning 4 , 5 and measurement of serum thyroglobulin 6 , 7 to detect residual or recurrent thyroid carcinoma. As a consequence of discontinuing thyroid hormone therapy, patients typically have symptomatic hypothyroidism, some may not have a sufficient increase in thyrotropin . . .