Abstract
Objective Antithyroglobulin antibodies (TgAbs) could be used as a surrogate tumor marker of TgAb-positive-differentiated thyroid carcinoma. This study aims to determine whether the change in TgAb levels over time could be used as a predictor of responses to therapy in pediatric papillary thyroid carcinoma (PTC) patients. Methods We retrospectively analyzed the records of 48 pediatric PTC patients with TgAb levels ≥50 IU/ml 6 months after initial 131I treatment. Suppressed thyroglobulin (Tg) levels 6 months after initial 131I treatment were used to divide the patients into positive Tg (P-Tg, Tg ≥ 0.2 ng/ml) and negative Tg (N-Tg, Tg < 0.2 ng/ml) groups. Responses to therapy were classified as the acceptable response (AR) group and the not acceptable response (NAR) group. Results Of 48 enrolled patients with 58 months (range, 24–143 months) of follow-up, 28 patients had NAR and 20 patients had AR. TgAb levels were decreasing ≥50% in 28 patients, decreasing <50% in 8 patients, and increasing in 12 patients. Multivariate analysis showed that high initial risk stratification and TgAb levels decreasing <50% or increasing were significantly associated with NAR (p < 0.05). Changes in Tg levels were also associated with NAR in the P-Tg group (p < 0.05). Conclusion Changes in TgAb levels over time could be used as a predictor of responses to therapy in TgAb-positive pediatric PTC patients. Changes in Tg levels over time are also associated with NAR to therapy in both TgAb-positive and Tg-positive pediatric PTC patients.
Highlights
Papillary thyroid carcinoma (PTC) is the most common thyroid cancer in both children and adults, accounting for 85%–90% of differentiated thyroid carcinoma (DTC) [1]
TgAb levels decreasing ≥50% and TgAbs clearance were observed in 20 (58.33%) and 23 (45.83%) patients at the end of follow-up, respectively. e median follow-up period was 58 months. ere were no significant differences between the positive Tg (P-Tg) and negative Tg (N-Tg) groups for the baseline clinicopathological characteristics that we evaluated (Table 1), except that the stimulated Tg level was significantly higher in the P-Tg group than in the N-Tg group (p .006)
Of the TgAb-positive patients (n 31) who were negative for Tg, three patients became Tg positive during follow-up, and among these patients, two had Structural incomplete response (SIR) at the end of follow-up. erefore, TgAbs may interfere with Tg determination, changes in Tg levels could be used as a prognostic factor in TgAb-positive pediatric PTC patients
Summary
Papillary thyroid carcinoma (PTC) is the most common thyroid cancer in both children and adults, accounting for 85%–90% of differentiated thyroid carcinoma (DTC) [1]. E persistence of or increase in Tg levels after total thyroidectomy and radioactive iodine (131I) treatment is a reliable indicator of persistent or recurrent disease in PTC. Most studies reported that the de novo appearance, persistence, or increase of TgAbs is a biochemical sign of persistent or recurrent disease in DTC [6, 8–18]. E prevalence of TgAbs in pediatric DTC patients was higher than in adult DTC patients [6, 7, 19]. The prognostic significance of TgAb levels is well demonstrated in adult DTC, its prognostic value in pediatric PTC is still unclear [19]. Us, it is inappropriate to extrapolate the prognostic value of TgAbs from adult data to pediatric patients. To our knowledge, no studies to date have focused on whether increasing TgAb levels could be used as a surrogate tumor marker to predict prognosis in pediatric PTC patients
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
