Endocrine Abstracts

Objectives: This study analyzed the prevalence of newly discovered anti-thyroglobulin antibody (TgAb) and its clinical significance during the follow-up period of patients with differentiated thyroid cancer.

Methods: Among patients who underwent total thyroidectomy and radioactive iodine treatment between 2008 and 2022 in a single center, 184 patients (23 male, 161 female) with Tg<1ng/ml and TgAb positive (> 60 IU/mL) at least once were targeted. Six hundred twenty patients with consistently normal TgAb were used as controls.

Results: An analysis was conducted on 38 patients of de novo detection of TgAb at least two consecutive follow-up tests during a mean follow-up of 7.2 years. Among them, 20 patients had a temporary increase, and 4 patients had a sustained or increased increase. Fourteen patients performed only two tests, so the temporary and continuous increase could not be identified. None of the patients with a transient increase had not confirmed structural recurrence pathologically, however two of the patients with maintained or increased TgAb levels had recurrence and subsequently underwent surgery. There was no significant association between de novo TgAb-positive patients and structural recurrence compared to normal patients.

Conclusions: Although there was no significant relationship between de novo TgAb detection and structural recurrence of DTC, additional studies are needed because patients with consistently high or increasing TgAb following de novo appearance are predicted to have an association with structural recurrence.