ABSTRACT
Serum thyroglobulin is used as part of the early postoperative assessment of differentiated thyroid cancer (DTC) since there is a clear relationship between an increased risk of recurrence and persistent disease after initial treatment and high postoperative stimulated thyroglobulin (ps-Tg) values. Thus, although ps-Tg above 10-30 ng/mL is considered an independent predictor of worse prognosis, the value that is associated with distant metastases is not defined. Thus, this was our objective. We selected 655 DTC patients from a nuclear medicine department database (Irmandade Santa Casa de Misericórdia de São Paulo, Brazil). All patients had received total thyroidectomy and radioactive iodine (RAI) therapy and had ps-Tg values higher than 10 ng/mL with negative anti-thyroglobulin antibodies. Then, we selected patients who presented post-therapy whole-body scan with pulmonary and/or bone uptake but with no mediastinum or cervical uptake. Patients with negative findings on functional imaging or any doubt on lung/bone uptake were submitted to additional exams to exclude another non-thyroid tumor. Of the 655 patients, 14.3% had pulmonary and 4.4% bone metastases. There was a significant difference in ps-Tg levels between patients with and without metastases (P<0.001). The cutoff value of ps-Tg was 117.5 ng/mL (sensitivity: 70.2%; specificity: 71.7%) for those with lung metastasis, and 150.5 ng/mL (sensitivity: 79.3%; specificity: 85%) for those with bone metastasis. The cutoff value for patients with eitherpulmonary or bone metastasis was 117.5 ng/mL (sensitivity: 70.2%; specificity: 83.7%). Our findings demonstrated that ps-Tg could predict distant metastasis in DTC patients. We identified a cutoff of 117.5 ng/mL with a high negative predictive value of 93.7%.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Thyroid Neoplasms/surgery , Thyroglobulin , Brazil , Iodine Radioisotopes , Neoplasm Recurrence, LocalABSTRACT
Objetivo. Estudar a densidade mineral óssea (BMD) vertebral (L2-L4) e femoral (colo do fêmur) de mulheres brancas, normais. Material e Método. Mediu-se o BMD de 724 mulheres (40-79 Kg; 20-69 anos de idade) por dual-energy x-ray absorptiometry e analisaram-se os dados em funçao da idade e peso corporal (PC). Resultados. As mulheres mais leves (40-49 Kg) atingiram o BMD maximo (BMDm) vertebral e femoral aos 30-39 anos de idade, enquanto as mais pesadas (60-79 Kg) apresentaram BMDm aos 20 anos. No fêmur, houve uma correlaçao significativa entre BMDm e PC (r=0,97, p<0,001; slope=0,72 por cento/Kg). Em L2-L4, apenas as mulheres com 40-49Kg apresentaram BMDm menor do que as demais(p<0,001). A diminuiçao do BMD vertebral foi mais intensa (-8,3 vs. -5,7 por cento/década) e iniciou mais cedo (quarta vs. quinta década) nas mulheres pesando 40-59Kg do que nas pesando 60-79Kg. A diminuiçao do BMD femoral iniciou logo após o BMDm ser atingido e, até os 69 anos, as mulheres mais pesadas apresentaram um decréscimo 5,3 por cento menor do que aquelas pesando 40-49Kg. O BMD vertebral das mulheres brasileiras foi praticamente o mesmo de uma populaçao norte-americana previamente descrita. Conclusoes. 1) O BMD vertebral e femoral das brasileiras estudadas comportou-se, em funçao da idade, de forma semelhante a de outras populaçoes brancas; 2) havendo o cuidado de corrigir o PC, o BMD das mulheres brasileiras é comparavel ao de mulheres norte-americanas; e 3) o PC é importante na aquisiçao e diminuiçao da massa óssea, além de influenciar a relaçao BMD-idade.