Endocrine Abstracts (2013) 32 P1111 | DOI: 10.1530/endoabs.32.P1111

Thyroglobulin as an early marker of persistent/recurrent disease in patients with differentiated thyroid carcinoma (DTC)

Anna Masó Aulinas1, Cristina Comí Colom2, Lilian Mathison Mendoza1, Valeria Aragón Alcantara1, Eugenia Matute Mato3, Rosa Plà Corcoy1,3, Ignasi Saladich Gich4, Jose Espinosa Rodriguez4 & Cintia Blanco González1,3


1Endocrinology and Nutrition Department. Santa Creu & Sant Pau Hospital, Barcelona, Spain; 2Endocrinology Unit, Dos de Maig Hospital, Barcelona, Spain; 3Biomedical Research Networking Centre on Bioengineering, Biomaterials & Nanomedicine: CIBER-BBN- EDUAB-HSP group, Spain; 4Clinical Epidemiology Department. Santa Creu & Sant Pau Hospital, Barcelona, Spain.


Introduction: Several clinical and molecular markers can be used to establish risk at the time of diagnosis in DTC. Thyroglobulin (Tg), which is essential in follow up, could be an early marker to identify risk patients. Around 25% of patients require 18 months or longer to have indetectable Tg. The presence of Tg antibodies (TgAb) invalidate the follow up of DTC via Tg and this is usually associated with a poor prognosis.

Aim: To evaluate the role of Tg after surgery and before radioiodine treatment, and the presence of TgAb as markers of persistent/recurrent disease in DTC.

Patients and methods: Retrospective study of 165 patients with DTC (1997–2010): women 78,2%, age at diagnosis 47.9+/- 16,26, medium follow up 4.8+/-3.74 years.

We performed a multivariate (logistic regression) analysis including Tg after surgery and before radioiodine treatment and other known prognostic variables. We divided Tg into tertile (cut-off: 1.7 ug/l, 13.6 ug/l) excluding TgAb positive at first before adding it later. We performed a ROC curve to identify cut-off level of Tg. Statistical analysis was performed with SPSS 19.0.

Results: In the multivariate analysis excluding TgAb positive, Tg in higher tertil is the unique predictive variable of persistent/recurrent disease at 18–24 months (RR 21.67). Adding positive TgAb, the predictive variables are Tg (RR 21, 04) and presence of TgAb (RR 112). The ROC curve shows a cut-off of Tg after surgery and before radioiodine treatment of 5,55 ug/l that identifies persistent/recurrent disease (S 81, E 57,5, NPV 92,5 and PPV 31,5% (AUC 0.809)).

Conclusions: In this serie, Tg value after surgery and before radioiodine treatment and the presence of TgAb are predictive variables of recurrent/persistent disease at 18–24 months. Tg has a predictive value and could be a useful marker to stratify risk at the time of diagnosis.