Intermediate-risk thyroid carcinoma: indicators of a poor prognosis

• Autor(a) principal: Faro,Fernanda Nascimento
• Data de Publicação: 2020
• Outros Autores: Bezerra,Ângela Maria Leal Barros, Scalissi,Nilza Maria, Cury,Adriano Namo, Marone,Marília Martins, Ferraz,Carolina, Padovani,Rosália do Prado
• 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=S2359-39972020000600764
• topic: Thyroid neoplasms; thyroid cancer; differentiated thyroid cancer; radioactive iodine therapy; thyroglobulin; prognosis

ABSTRACT Objective: The intermediate-risk (IR) category includes tumors with different degrees of aggression. We aimed to identify the risk factors associated with unfavorable response to initial treatment and compare the effect of low/high radioactive iodine (RAI) therapy. Subjects and methods: A total of 614 IR patients were selected from a database, during 1972-2015. All patients underwent total thyroidectomy and RAI therapy and were reclassified after 12-18 months into the favorable (complete/indeterminate) response group and the unfavorable (biochemical/incomplete structural) response group. A total of 92 patients were assessed for late response (mean: 9.19 ± 5.73 years). Age, gender, tumor size, histology, multifocality, vascular invasion, extrathyroidal extension, presence and number of lymph node metastasis, and stimulated thyroglobulin at ablation (sTg) were evaluated. Results: Mean age at diagnosis was 41.47 ± 15.81 years, and 83.6% of the patients were female. Within 12-18 months after initial therapy, unfavorable response was detected in 41.2% of the patients and was associated, in multivariate analysis, with lymph node metastasis (p = 0.041; odds ratio [OR] = 1.9), presence of more than five metastatic lymph nodes (p = 0,017; OR = 2.6), and sTg > 10 ng/mL (p = 0.005; OR = 10.0). For patients with a longer follow-up, sTg >10 ng/mL was associated with unfavorable response (p = 0.002; OR = 6.8). A higher RAI dose was not related to better prognosis at the end of the follow-up. Conclusion: A sTg level of >10 ng/mL and lymph node metastasis were associated with an unfavorable response 12-18 months after initial treatment. A RAI dose below 150 mCi was proven sufficient to treat IR patients.