Importance of recombinant human thyrotropin as an adjuvant in the radioiodine treatment of thyroid cancer.

Radioiodine (RAI) therapy for treatment of differentiated thyroid cancer (DTC) requires high serum thyroid-stimulating hormone (TSH) levels to induce a sufficient iodine uptake within thyroid cells. Recombinant Human TSH (rhTSH) induces an exogenous TSH level increase without LT4 withdrawal. It is a valid alternative to LT4-withdrawal (LT4-W) to achieve the TSH levels required for RAI therapy. According to the recent American Thyroid Association (ATA) guidelines, candidates for RAI therapy should be selected based on their DTC risk of recurrence. Areas covered: In this review, we report the studies assessing the effects of rhTSH on RAI ablation compared to thyroid hormone withdrawal in patients with thyroid cancer at different ATA risk of recurrence. We focus our attention on high risk patients and metastatic disease in which RAI treatment is routinely recommended although there are few controversial data about the best possible way of preparing for it. Expert commentary: rhTSH-aided therapy is associated to a better quality of life and to a lower body radiation exposure. Several studies have reported an equivalent efficacy of RAI ablation after TSH stimulation with rhTSH or LT4-W in patients with DTC at low and intermediate risk of recurrence. Although more studies are required, the results are promising even in patients with high risk DTC and metastatic disease.