Appropriate dosing of adjuvant radioactive iodine for differentiated thyroid cancer

The incidence of well differentiated thyroid cancer (WDTC) is increasing in the US population and is now a major public health concern. Although surgery is the mainstay of treatment, radioactive iodine (RAI) is routinely used for adjuvant therapy, remnant ablation, and for the treatment of metastatic disease. Despite excellent prognosis and stable mortality rates, the use of RAI is increasing in many low and intermediate risk WDTC patients without clear indication that it changes the outcome. As a result, the current treatment paradigm has shifted towards a risk-stratified approach.

Although there is widespread acceptance that RAI improves overall and recurrence-free survival in patients with metastatic disease, controversy remains regarding radioactive remnant ablation use in low and intermediate risk patients. Additional studies have shown that reduced doses of RAI can provide similar rates of remnant ablation and adjuvant therapy in low and intermediate risk patients without adversely affecting the recurrence rates and mortality.

Recent studies suggest potential new paradigms in radioactive remnant ablation dosing and indications for use. Risk stratification is important in determining the proper use and dosing of RAI.