Post-Operative Stimulated Thyroglobulin As a Prognostic Factor for Differentiated Thyroid Cancer in Children and Adolescents

Program: Abstracts - Orals, Poster Previews, and Posters
Session: SAT 270-310-Thyroid Neoplasia (posters)
Clinical/Translational
Saturday, April 2, 2016: 1:15 PM-3:15 PM
Exhibit/Poster Hall (BCEC)

Poster Board SAT 299
Jose Miguel S Dora*1, Andre Borsatto Zanella2, Rafael Selbach Scheffel3 and Ana Luiza Maia4
1Hospital de Clinicas de Porto Alegre, Porto Alegre RS, Brazil, 2Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil, 3Hospital de ClĂ­nicas de Porto Alegre, Porto Alegre, Brazil, 4Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
Introduction: Differentiated thyroid carcinoma (DTC) in children and adolescents presents more frequently with cervical and distant metastasis as compared to adults. The post-operative stimulated thyroglobulin (sTg) has been suggested as a prognostic marker in adult patients with DTC, but the optimum cut-off point for risk stratification for children remains to be clarified. Here, we aimed to evaluate the performance of sTg as a prognostic factor in children and adolescents with DTC followed at our institution.

Methods: DTC patients younger than 18 years of age at diagnosis were selected from a cohort of 880 DTC patients attending the Thyroid Clinic, at a tertiary university–based hospital. Baseline clinical and oncological characteristics, interventions, disease status and outcomes are described. The sTg was evaluated through the area under the ROC curve, using sTg as a continuous prognostic variable and disease status at follow-up as the outcome variable.

Results: A group of 30 children and adolescents with DTC, composed by 25 (83.3%) girls and mean age at diagnosis of 14.6 ± 3.3 years, were included in this report. Twenty-nine (96.7%) patients had papillary thyroid carcinoma, presenting a median tumor size of 2.2 cm (P25-75 1.7-3.5), cervical metastasis in 19 (63.3%) and distant metastasis in 4 (13.3%) patients. Regarding the TNM stage, 26 (86.7%) were in stage I and 4 (13.3%) in stage II. All patients underwent total thyroidectomy and 27 (90.0%) received radioactive iodine (RAI) therapy (median dose of 100 mCi, P25-75 100-150). After a median follow-up of 5.0 years (P25-75 3.0-9.8), 15 (62.5%) patients are considered disease free, 5 (20.8%) have with biochemical persistent disease and 4 (16.7%) persistent structural disease. The post-operative sTg cut-off of 12 ng/ml had a sensitivity of 100% and a specificity of 90% to predict disease free status, with an area under the ROC curve of 0.99 (CI 0.95-1.00), P<0.001.

Conclusion: Our data demonstrated that sTg seems to be a useful prognostic factor for DTC in children and adolescents. Of special interest is that the optimal sTg cut-off point of 12 ng/ml for this population is higher than that obseverd in the adult population.

Nothing to Disclose: JMSD, ABZ, RSS, ALM

*Please take note of The Endocrine Society's News Embargo Policy at https://www.endocrine.org/news-room/endo-annual-meeting/pr-resources-for-endo

Sources of Research Support: CNPq, FAPERGS