Objective: To discuss the approach to care of patients with advanced differentiated thyroid cancer (DTC), in particular those with radioactive iodine (RAI)-refractory disease, and the transition to systemic treatment.
Methods: A PubMed search was conducted using the search terms "radioactive iodine-refractory, differentiated thyroid cancer and treatment" restricted to a 2000-2012 timeframe, English language, and humans. Relevant articles were identified from the bibliographies of selected references. Four patient cases are presented to illustrate the clinical course of RAI-refractory DTC.
Results: The current standard of care for early stage DTC could include surgery, RAI in some cases, and thyroid hormone suppression. For advanced RAI-refractory DTC, clinical practice guidelines established by the National Comprehensive Cancer Network and the American Thyroid Association recommend, as one option, the use of systemic therapy, including kinase inhibitors. Numerous trials are underway to evaluate the clinical benefit of these targeted therapies.
Conclusion: Preliminary results are encouraging with respect to the clinical benefit of targeted systemic therapies. However, at present there is no consensus on the criteria that define RAI-refractory disease and the optimal timing for transition to systemic therapy. There remains a need to establish common criteria to enhance patient care and enable better comparison across clinical studies.