- Stim-Tg will be checked at 3 months postoperatively (prior to RAI scan/ablation, if indicated) and at 1 year postoperatively or 1 year post-remnant ablation. 1 year stim-Tg evaluation will be performed in patients enrolled at the NIH but is optional in patients enrolled at non-NIH site(s) Unstimulated Tg, thyroid function tests, and anti-thyroglobulin antibodies will be checked annually for 10 years.