Role of Recombinant Human Thyrotropin (rhTSH) in the Treatment of Well-Differentiated Thyroid Cancer.

Since the introduction of radioiodine (RAI) for treatment of well-differentiated thyroid cancer (DTC) more than 50 years ago, prolonged periods of hypothyroidism were routinely used as part of the treatment regimen. Recombinant human TSH (rhTSH) was introduced in the 1990s as a tool to elevate the serum TSH without the need for thyroid hormone withdrawal and symptomatic hypothyroidism. After being initially approved as a diagnostic tool for use in RAI scanning and stimulated thyroglobulin testing, rhTSH was approved as an adjunct to RAI remnant ablation in patients without distant metastases in Europe in 2005 and in the US in 2007. Following successful use of rhTSH for diagnostic purposes, it has been extensively studied for use with therapeutic doses of RAI in the setting of RAI remnant ablation and is now an integral part of DCT therapy. The use of rhTSH in clinical practice in the last decade was coupled with the growing interest in an individualized, risk-stratified approach to the management of patients with DCT. While traditional treatment for DTC included surgery and RAI therapy for all patients, many more recent studies demonstrated the value of selective use of RAI only in patients who will probably benefit from treatment. This manuscript reviews the evolving role of rhTSH in the current risk adapted climate of thyroid cancer management with particular emphasis on the use of rhTSH as an aid to RAI therapy.