Fig. 1

Flow chart of patients reviewed. PTC papillary thyroid carcinoma, TT total thyroidectomy, LNs lymph nodes, Tg thyroglobulin, TgAb anti-thyroglobulin antibody, uTg maximum unstimulated Tg, RAI radioactive iodine, off-Tg Pre-RAI ablation serum-stimulated Tg, on-Tg unstimulated Tg detected at 1 week after RAI ablation