Table 4. Follow up strategies based on response to initial therapys.

Response to Therapy	Recommended follow-up
Excellent Response	Early decrease in the intensity and frequency of follow up and degree of TSH suppression Low and intermediate risk: Non stimulated Tg and TgAb every 12-24 months; Consider neck US in 12-24 months, if negative, no need for further imaging
Indeterminate Response	Decrease in the intensity and frequency of follow up and degree of TSH suppression Active surveillance: Serial imaging of non specific lesions; Non stimulated Tg and TgAb every 12-24 months
Biochemical Incomplete Response	Follow Tg curve with similar TSH levels. Stable or declining Tg levels = Active surveillance Non stimulated Tg and TgAb every 6-12 months, Stimulated Tg if clinically indicated; Neck US in 12 months. TSH suppression (mild) Increasing Tg or TgAb levels = Additional investigation Individualized approach with anatomic, functional and/or hybrid imaging. TSH suppression.
Structural Incomplete Response	Individualized approach: Consider actionable and non-actionable structural evidence of disease. TSH suppression