Thyroglobulin/thyrotropin ratio for predicting long-term response in differentiated thyroid carcinoma: a retrospective study

• Autor(a) principal: Marchi Junior,Adriano Francisco De
• Data de Publicação: 2021
• Outros Autores: Macedo,Ana Bárbara Trizzotti de, Soares,Carlos Segundo Paiva, Bolfi,Fernanda, Iessi,Mariana Riello Gomes, Oliveira,Cristiano Claudino de, Koga,Katia Hiromoto, Moriguchi,Sonia Marta, Tagliarini,José Vicente, Mazeto,Gláucia Maria Ferreira da Silva
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Arquivos de Endocrinologia e Metabolismo (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S2359-39972021000400428
• topic: Thyroid neoplasms; thyroglobulin; prognosis

ABSTRACT Objective: Thyrotropin-stimulated thyroglobulin (STg) after total thyroidectomy is a prognosis marker for differentiated thyroid carcinoma (DTC). As Tg level is influenced by thyrotropin (TSH), perhaps the STg/TSH ratio is also a prognosis marker for these tumours. We aimed to compare STg/TSH ratio and first STg level in differentiated thyroid carcinoma patients for their ability to predict the long-term response to initial treatment. Subjects and methods: This retrospective study evaluated data from 181 DTC patients for first (1st) STg and STg/TSH ratio, at 1-3 months post-total thyroidectomy and before iodine-131 therapy, according to response to initial therapy [Excellent/Indeterminate or Incomplete (Biochemical/Structural)] observed at final evaluation, and with the survival time with excellent/indeterminate response. Results: Cases with incomplete response presented higher STg level [225.13 ± 585.26 ng/mL versus (vs) 20.4 ± 192.9 ng/mL; p < 0.001] and STg/TSH ratio (3.01 ± 7.8 vs 0.27 ± 2.58; p < 0.001). Cutoffs of 5 ng/mL for STg and 0.085 for STg/TSH displayed sensitivities of 76.7% and 76.9%, and specificities of 79.2% and 82.6%, respectively, in predicting response to therapy. Values below these cutoffs were associated with longer survival time in excellent/indeterminate response (140.4 vs 15.9 and 144.6 vs 15.9 months, respectively). Conclusion: STg/TSH ratio has a similar performance to the 1st STg in predicting long-term response to initial therapy.