The evolving use of radioiodine therapy in differentiated thyroid cancer.

The incidence of differentiated thyroid cancer has increased worldwide over the last three decades, but thyroid cancer-related mortality remains stable. Until recently, the standard treatment for most thyroid cancers has been near-total thyroidectomy followed by radioiodine remnant ablation. Observational data support lower recurrence rates and improved survival after radioiodine ablation in patients with high-risk cancers; however, a similar benefit has not been established for all patients with thyroid cancer. Risk stratification should be used to identify patients who are likely to benefit from radioiodine ablation and guide therapeutic decisions. For most patients who need radioiodine remnant ablation, preparation for therapy with recombinant human thyroid-stimulating hormone stimulation is as effective as thyroid hormone withdrawal. Lower therapeutic doses of radioiodine are recommended for the majority of thyroid remnant ablations. Higher doses are reserved for advanced disease at initial diagnosis, local recurrences that cannot be treated with surgery alone, and distant metastatic disease.